DN 22 : Mahasatipatthana Sutta: The Greater Discourse on the Foundations of Mindfulness

Thus have i heard. 

Once the Buddha addressed the monks: 'Monks! There is this one and only way to the purification of beings, for the overcoming of sorrow and distress, for the disappearance of pain and sadness, for the attainment of the noble path, for the realization of Nibbana: that is to say the four foundations of mindfulness. What are the four? Here, a monk abides contemplating body as body, with diligence, comprehension and mindfulness and thus keeping away covetousness and distress. Having put aside hankering and fretting for the he abides contemplating feelings as feelings with diligence, comprehension and mindfulness and thus keeping away covetousness and distress.; Then he abides contemplating mind as mind with diligence, comprehension and mindfulness and thus keeping away covetousness and distress.; Then he abides contemplating mind-objects as mind-objects with diligence, comprehension and mindfulness and thus keeping away covetousness and distress.

Contemplation of the Body 

1. Mindfulness of Breathing

Buddha: "How, monks, does a monk abide contemplating the body as body? Here a monk, having gone into the forest, or to the root of a tree, or to an empty place and sits down cross-legged, holding his body erect, having established mindfulness before him. Mindfully he breathes in, mindfully he breathes out.  Breathing in a long breath, he knows that he breathes in a long breath and breathing out a long breath, he knows that he breathes out a long breath. Breathing in a short breath, he knows that he breathes in a short breath, and breathing out a short breath, he knows that he breathes out a short breath.

He trains himself to be clearly conscious of the whole stretch of the in-coming and out-going breath at its beginning, its middle, and at its end.  By being fully conscious of the inhalation and exhalation, he trains himself to calm down the strong inhalation and exhalation as he breathes. Just like a skilled turner, or his assistant, in making a long turn, knows that he is making a long turn, or in making a short turn, knows that he is making a short turn, so too a monk is mindfully conscious of his breathing in and out. 

So a monk abides contemplating body as body internally,  contemplating body as body externally, contemplating body as body both internally and externally. He abides contemplating arising phenomena in the body, he abides contemplating vanishing phenomena in the body, he abides contemplating both arising and vanishing phenomena in the body. The monk is firmly mindful of the fact that there is only the aggregate of physical phenomena. That mindfulness (awareness) is solely for gaining insights progressively, solely for gaining further mindfulness stage by stage. The bhikkhu remains detached from craving and wrong views, without clinging to any of the five aggregates that are continuously deteriorating. And he abides independent, not clinging to anything in the world. And that, monks, is how a monk abides contemplating body as body."  

2. The four postures

Buddha: 'Again, a monk, when walking knows that he is walking, when standing knows that he is standing, when sitting knows that he is sitting and when lying down knows that he is lying down (four postures). In whatever way his body is disposed, he knows that that is how it is. So he abides contemplating body as body internally, externally, and both internally and externally. '

3. Clear Awareness

Buddha: 'Again, a monk, when going forward or back is clearly aware of what he is going forward or back. He is clearly aware of what he is doing, in bending and stretching, aware that he is carrying his inner and outer robe and his bowl, he is clearly aware of what he is doing, in eating, drinking, chewing and savoring, in passing excrement or urine, in walking, standing, sitting, falling asleep and waking up, in speaking or in staying silent, he is clearly aware of what he is doing. Thus he keeps his mind steadfastly on the aggregate of physical phenomena which is his body... Bhikkhus, it is also in this way that the monk contemplates on the body.'

​4. Reflection on the Repulsive: Parts of the Body

Buddha: 'Again, a monk reviews this very body from the soles of the feet upwards and from the scalp downwards, enclosed by the skin and full of manifold impurities: "There are hairs on the head, body-hairs, nails, teeth, skin, flesh, sinews, bones, bone-marrow, kidneys, heart, liver, pleura, spleen, lungs, mesentery, bowels, stomach, excrement, bile, phlegm, pus, blood, sweat, fat, tears, tallow, saliva, snot, synovic fluid and urine."

Just as if there were a bag, open at both ends, full of various kinds of grain such as hill-rice, paddy, green kidney-beans, sesame, husked rice, and a man with good eyesight were to open the bag and examine them, saying: "This is hill-rice, this is paddy, this is green gram, these are kidney-beans, this is sesame, this is husked rice", so too a monk reviews this very body: "In this body there are hairs,nails, teeth. . . urine." So he abides contemplating body as body internally, externally, and both internally and externally. . .that, monks, is how a monk abides contemplating body as body. 

5. The Four Elements
 
Buddha:  'Again, a monk reviews this body in terms of the four elements: "There are in this body the earth-element, the water-element, the fire-element and the air-element." Just as if a skilled butcher or his assistant, having slaughtered a cow to sit at a crossroads with the carcass divided into portions, so a monk re- views this very body in terms of the elements (solids, liquids, heat and breath) . Thus he keeps his mind steadfastly on the aggregate of physical phenomena which is his body... Bhikkhus, it is also in this way that the bhikkhu keeps his mind steadfastly on the body.

6.  The Nine Charnel-Ground contemplation

Buddha: 'Again, a monk, as if he were to see a corpse thrown aside in a charnel-ground, one day dead, two days dead or three days dead, bloated, discolored, festering, compares this body with that thinking: "This body of mine is of the same nature, it will become like that one day and it is not exempt from that fate." So he abides contemplating body as body internally, externally, and both internally and externally. That, monks, is how a monk abides contemplating body as body.

Again, a monk, as if he were to see a corpse in a charnel- ground, thrown aside, eaten by crows, hawks or vultures, by dogs or jackals, or various other creatures, compares this body with that, thinking: "This body of mine is the same nature, it will become like that one day and it is not exempt from that fate."

Again, a monk, as if he were to see a corpse in a charnel- ground, thrown aside, a skeleton with flesh and blood, connected by sinews, a flesh-less skeleton smeared with blood, connected by sinews, a skeleton detached from the flesh and blood connected by sinews, randomly connected bones scattered in all directions, a hand-bone here, a foot bone there, a shin-bone here, a thigh-bone there, a hip-bone here, a spine here, a skull there, compares this body with that thinking his body is the same.

Again, a monk, as if he were to see a corpse in a charnel-ground, thrown aside, the bones whitened, looking like shells, the bones piled up a year old, the bones rotted away to a powder, compares this body with that of his thinking: "This body is of the same nature, will become like that, is not exempt from that fate."

So a monk abides contemplating body as body internally,  contemplating body as body externally, contemplating body as body both internally and externally. He abides contemplating arising phenomena in the body, he abides contemplating vanishing phenomena in the body, he abides contemplating both arising and vanishing phenomena in the body. The monk is firmly mindful of the fact that there is only the aggregate of physical phenomena. That mindfulness (awareness) is solely for gaining insights progressively, solely for gaining further mindfulness stage by stage. The bhikkhu remains detached from craving and wrong views, without clinging to any of the five aggregates that are continuously deteriorating. And he abides independent, not clinging to anything in the world. And that, monks, is how a monk abides contemplating body as body."  

Contemplation of feelings

 Buddha: 'And how, monks, does a monk abide contemplating feelings as feelings? Here, a monk feeling a pleasant feeling knows that he feels a pleasant feeling; feeling a painful feeling he knows that he feels a painful feeling;  feeling a feeling that is neither-painful-nor-pleasant he knows that he feels a feeling that is neither-painful-nor-pleasant; feeling a pleasant sensual feeling he knows that he feels a pleasant sensual feeling; feeling a pleasant non-sensual feeling he  knows that he feels a pleasant non-sensual feeling; feeling a painful sensual feeling he knows its a painful sensual feeling, feeling a painful non-sensual feeling he knows its a painful non-sensual feeling, feeling a sensual feeling that is neither-painful-nor- pleasant he knows its a sensual feeling that's neither painful nor pleasant and feeling a non-sensual feeling that is neither-painful-nor-pleasant, he knows that he feels a non-sensual feeling that is neither painful-nor-pleasant.' 

So he abides contemplating feelings as feelings internally. He abides contemplating feelings as feelings externally. He abides contemplating arising phenomena in the feelings, vanishing phenomena and both arising and vanishing phenomena in the feelings. That mindfulness is solely for gaining insights progressively, solely for gaining further mindfulness stage by stage. The monk remains detached from craving and wrong views, without clinging to any of the five aggregates that are continuously deteriorating. The monk keeps his mind steadfastly on sensation perceiving its true nature. And he abides independent, not clinging to anything in the world. And that, monks, is how a monk abides contemplating feelings as feelings.' 

Contemplation of the mind 

Buddha: 'And how, monks, does a monk abide contemplating mind as mind? Here, a monk knows a lustful mind as lustful, a mind free from lust as free from lust; a hating mind as hating, a mind free from hate as free from hate; a deluded mind as deluded, an un-deluded mind as un-deluded; a contracted mind as contracted, a distracted mind as distracted; a developed mind as developed, an undeveloped mind as undeveloped; a surpassed mind as surpassed, an unsurpassed mind as unsurpassed; a concentrated mind as concentrated, an un-concentrated mind as un-concentrated; a liberated mind as liberated and an un-liberated mind as un-liberated.' 

​Thus the monk abides contemplating on his own mind. Occasionally he realizes that the mind of others must be of a similar nature. Because of this realization, he can be said to concentrate steadfastly on the mind of others. In this way, he is considered to be aware of his own mind or on the mind of others. When he gains more concentration, he perceives the cause and the actual appearing of the mind. He also perceives the cause and the actual dissolution of the mind. He also perceives both the actual appearing and the actual dissolution of the mind, with their causes. And further, the monk is firmly mindful of the fact that there is only Mind without soul (atta). That mindfulness is solely for gaining insights progressively, solely for gaining further mindfulness stage by stage. The bhikkhu remains detached from craving and wrong views, without clinging to any of the five aggregates that are continuously deteriorating.  And that, monks, is how a monk abides contemplating mind as mind.' 

​Contemplation of mind-objects

Buddha :'And how, monks, does a monk abide contemplating mind-objects as mind-objects?

1. The Five Hindrances

Buddha: 'Here, a monk abides contemplating mind-objects as mind- objects in respect of the five hindrances. Here, monks, if sensual desire is present in himself, a monk knows that it is present. If sensual desire is absent in himself, a monk knows that it is absent. He knows how un-arisen sensual desire comes to arise, he knows how the abandonment of arisen sensual desire comes about and he knows how the non-arising of the abandoned sensual desire in the future will come. 

If ill will is present in himself, a monk knows that it is present and he knows how the non-arising of the abandoned ill-will in the future will come about.

If sloth-and-torpor is present in himself, a monk knows that it is present and he knows how the non-arising of the abandoned sloth-and-torpor in the future will come about.

If worry-and-distraction is present in himself, a monk knows that it is present and he knows how the non-arising of the abandoned worry-and-flurry in the future will come about.

If doubt is present in himself, a monk knows that it is present. If doubt is absent in himself, he knows that it is absent. And he knows how un-arisen doubt comes to arise, he knows how the abandonment of arisen doubt comes about, he knows how the non-arising risen doubt comes about and he knows how the non-arising of the abandoned doubt in the future will come about.

Thus he keeps his mind steadfastly on the dhamma, mental and physical phenomena in himself. Occasionally he realizes that the dhamma in others must be of a similar nature. Because of this realization, he can keep his mind steadfastly on the dhamma in others. In this way, he is aware of the dhamma; in himself or in others. When he gains more concentration, he perceives the cause and the actual appearing of the dhamma. He also perceives the cause and the actual dissolution of the dhamma. He also perceives both the arising and the actual dissolution of the dhamma with their causes. The monk is firmly mindful of the fact that there are only dhamma. That mindfulness is solely for gaining insights progressively, solely for gaining further mindfulness stage by stage. The monk remains detached from craving and wrong views, without clinging to any of the five aggregates that are continuously deteriorating. And that monks, is how a monk abides contemplating mind-objects as mind-objects in respect of the five hindrances. 

2. The Five Aggregrates

Buddha: 'Again, monks, a monk abides contemplating mind-objects as mind-objects in respect of the five aggregates of grasping. Here, a monk thinks: "Such is form, such is the arising of form, such the disappearance of form, Such is feeling, such is the arising of feeling, such the disappearance of feeling. Such is perception, such is the arising of perception, such the disappearance of perception. Such are the mental formations,  such is the arising of the mental formations, such the disappearance of the mental formations. Such is consciousness, such is the arising of consciousness, such the disappearance of consciousness.' 

So a monk abides contemplating mind-objects as mind-objects internally and he abides detached, not grasping at anything in the world. And that, monks, is how a monk abides contemplating mind-objects as mind-objects in respect of the five aggregates of grasping.' 

​3. The Six lnternal and External Sense-Bases 
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Buddha: 'Again a monk abides contemplating mind-objects as mind-objects in respect of the six internal and external sense-bases. Here a monk knows the eye, knows visible objects and he knows whatever fetter arises dependent on the two. He knows how an un- arisen fetter comes to arise, he knows how the abandonment of an arisen fetter comes about and he knows how the non-arising of the abandoned fetter in the future will come about. He knows the ear and knows sounds. He knows the nose and knows smells. He knows the tongue and knows tastes. He knows the body  and knows tangibles. He knows the mind and knows mind-objects and he knows whatever fetter arises dependent on the two, how an un-arisen fetter comes to arise he knows how the abandonment of an arisen fetter comes about and he knows how the non-arising of the abandoned fetter in the future will come about.
 
So he abides contemplating mind-objects as mind-objects internally and externally, he abides detached, not grasping at anything in the world. That monks, is how a monk abides I contemplating mind-objects as mind-objects in respect of the six internal and external sense-bases.

​4. The Seven Factors of Enlightenment

Buddha: 'Again a monk abides contemplating mind-objects as mind-objects in respect of the 7 factors of enlightenment. Here, monks, if the enlightenment-factor of mindfulness is present in himself, a monk knows that it is present. If the enlightenment-factor of mindfulness is absent in himself, he knows that it is absent. He knows how the un-arisen enlightenment-factor of mindfulness comes to arise, he knows how the complete development of the enlightenment-factor of mindfulness comes about. He knows if the enlightenment-factor of investigation of states is present in himself. He knows if the enlightenment-factor of energy is present in himself. He knows if the enlightenment-factor of delight is present in himself. He knows if the enlightenment-factor of tranquility is present in himself. He knows if the enlightenment- factor of concentration is present in himself. If the enlightenment-factor of equanimity is present in himself, a monk knows that it is present. If the enlightenment-factor of equanimity is absent in himself, he knows that it is absent. He knows how the un-arisen enlightenment-factor of equanimity comes to arise and he knows how the complete development of the enlightenment-factor of equanimity comes about. 

So he abides contemplating mind-objects as mind-objects internally and externally. He abides detached, not grasping at anything in the world. And that, monks, is how a monk abides contemplating mind-objects as mind-objects in respect of the seven factors of enlightenment.' 

5. The Four Noble Truths

Buddha: 'Again, monks, a monk abides contemplating mind-objects as mind-objects in respect of the Four Noble Truths.  Here, a monk knows as it really is: "This is suffering";  "This is the origin of suffering";  "This is the cessation of suffering";  "This is the way of practice leading to the cessation of suffering."

What, monks, is the Noble Truth of Suffering? Birth is suffering, ageing is suffering, death is suffering, sorrow, lamentation, pain, sadness and distress are suffering. Being attached to the unloved is suffering, being separated from the loved is suffering, not getting what one wants is suffering. In short, the five aggregates of grasping  are suffering.

What is birth? The coming into existence, the complete origination, the conception, the arising up in new form, the appearance of the Aggregates, the acquisition of the sense-bases of various beings in various categories, this, monks, is called birth.

What is aging? The process of aging, the decrepitude, the decay and loss of teeth, the graying of hair, the wrinkling of skin, the failing of the life-force, the wearing out of the sense-faculties such as sight of various beings in various catagories, this, monks, is called aging.

What is death? The falling away from existence, the passing away from existence, the dissolution, the disappearance, the end of life, the passing away due to completion of the life-span, the breaking up of the Aggregates, the discarding of the body, the destruction of the life-faculty of various beings in various categories, this, bhikkhus, is called death. 

What is sorrow? Whenever, by any kind of misfortune, anyone is affected by something of a painful nature, sorrow, mourning, distress, inward grief, inward woe, that, monks, is called sorrow.

What is lamentation? Whenever, by any kind of misfortune, anyone is affected by something of a painful nature and there is crying out, lamenting, making much noise for  grief, making great lamentation, that, monks, is called lamentation. 

What is pain? Whatever bodily painful feeling, bodily unpleasant feeling, painful or unpleasant feeling results from bodily contact, that, monks, is called pain. 

What is sadness? Whatever mental painful feeling, mental unpleasant feeling, painful or unpleasant sensation results from mental contact, that, monks, is called sadness. 

What is distress? The mental pain and mental unpleasantness, the painful and unpleasant feeling produced by contact of the mind, — this, bhikkhus, is called distress.

What, monks, is being attached to the unloved? Here, whoever has unwanted, disliked, unpleasant sight-objects, sounds, smells, tastes, tangibles or mind-objects, or ,whoever encounters ill-wishers, wishers of harm, of discomfort, of insecurity, with whom they have concourse, intercourse, connection, union, that, monks, is called being attached to the unloved. 

What is being separated from the loved? Here whoever has what is wanted, liked, pleasant sight-objects, sounds, smells, tastes, tangibles or mind-objects, or whoever encounters well-wishers, wishers of good, of comfort, of security, family members or friends or colleagues and then is deprived of such concourse, intercourse, connection, or union, that, monks, is called being separated from the loved.

What is not getting what one wants? Those subjected to rebirth, wishing not to be born again but this cannot be gained by wishing. That is not getting what one wants. In beings subject to ageing, to to death, to sorrow, lamentation, pain, sadness and distress , they wish that they can evade such situations but this cannot be gained by wishing. That is not getting what one wants.

How monks, in short, are the five aggregates of grasping suffering? They are grasping of form, grasping of feelings, grasping of perception, grasping of mental formations, grasping of consciousness. These are in short the five aggregates of grasping that are suffering. That, monks, is called the Noble Truth of Suffering.

What monks is the Noble Truth of the Origin of Suffering? It is craving that gives rise to rebirth, bound up with pleasure and lust, finding fresh delight now here, now there. The three cravings are sensual craving, craving for existence and craving for non-existence. Where does this craving arise and establish itself? Wherever in the world there is anything agreeable and pleasurable, craving arises. When the eye sees something desirable, when the ear hears something delightful, when the nose smells something fragrant, when the tongue tastes something delicious , when the body touches something tangible and when the mind thinks of something agreeable and pleasurable, then craving arises and establishes itself. Sights, sounds, smells, tastes, tangibles, mind-objects in the world are agreeable and pleasurable and there this craving arises and establishes it- self. Then the correspondent eye-consciousness, ear-consciousness, nose-consciousness, tongue-consciousness, body-consciousness, mind-conscious- ness in the world is agreeable and pleasurable, and there this craving arises and establishes itself. When the correspondent eye-contact, ear-contact, nose-contact, tongue-contact, body-contact and mind-contact in the world is agreeable and pleasurable then craving arises and establishes itself.

From contact, feeling arises: Feeling born of eye-contact, ear-contact, nose-contact, tongue-contact, body-contact, mind-contact the world is agree- able and pleasurable, and there this craving arises and establishes itself. The perception of sights, of sounds, of smells, of tastes, of tangibles, of mind-objects in the world is agreeable and pleasurable, and there this craving arises and establishes itself. Volition in regard to sights, sounds, smells, tastes, tangibles, mind-objects in the world is agreeable and pleasurable, and there this craving arises and establishes itself. 

The craving for sights, sounds, smells, tastes, tangibles, mind-objects that are pleasurable give rise to this craving. Thinking of sights, sounds, smells, tastes, tangibles, mind-objects that are pleasurable give rise to this craving.  Wondering on sights, sounds, smells, tastes, tangibles and mind-objects that are pleasurable give rise to this craving. That monks, is called the Noble Truth of the Origin of Suffering. 

What monks, is the Noble Truth of the Cessation of Suffering? It is the complete cessation and extinction of this craving, its forsaking and abandonment, liberation from it and detachment from it. How does this craving come to be abandoned and how does cessation come about? Wherever in the world there is anything agreeable and pleasurable, there cessation comes about.

What is there in the world that is agreeable and pleasurable? The eye has the characteristic of being delightful and pleasurable. When this Craving is abandoned, it is abandoned there; when it ceases, it ceases there. Similarly for the ear, the nose, the tongue, the body and the mind. Eye-consciousness, ear-consciousness, nose-consciousness, tongue-consciousness, body-consciousness, mind-consciousness in the world is agreeable and pleasurable and there this craving comes to be abandoned, there its cessation comes about. Sights, sounds, smells, tastes, tangibles, mind-objects in the world are agreeable and pleasurable, and there this craving comes to be abandoned, there its cessation comes about. Eye-contact, ear-contact, nose-contact, tongue-contact, body- contact, mind-contact; the perception of sights, sounds, smells, tastes, tangibles, mind-objects; volition in regard to sights, sounds, smells, tastes, tangibles, mind-objects; craving for sights, sounds, smells, tastes, tangibles, mind- objects; thinking of sights, sounds, smells, tastes, tangibles, mind-objects; pondering on sights, sounds, smells, tastes, tangibles and mind-objects in the world is agreeable and pleasurable, and there this craving comes to an end, there its cessation comes about. That monks, is called the Noble Truth of the Cessation of Suffering.

What monks, is the Noble Truth of the Way of  the path leading to the Cessation of Suffering? It is the Noble Eightfold Path, namely: Right View, Right Thought, Right Speech, Right Action, Right Livelihood, Right Effort, Right Mindfulness and Right Concentration. What is Right View? It is the understanding of the knowledge of suffering, the knowledge of the origin of suffering, the knowledge of the cessation of suffering, and the knowledge of the way of practice leading to the cessation of suffering (4 noble truths). What is Right Thought? It is the thoughts of renunciation, the thought of non-ill-will, the thought of harmlessness. What is Right Speech? It is refraining from lying,  refraining from slander, refraining from harsh speech, refraining from frivolous speech.

What is Right Action? It is refraining from taking life, refraining from taking what is not given, refraining from sexual misconduct (precepts). What is Right Livelihood? Here, the Ariyan disciple having given up wrong livelihood, keeps himself by right livelihood. What, monks is Right Effort? Here, a monk rouses his will, makes an effort, stirs up energy, exerts his mind and strives to prevent the arising of un-arisen evil unwholesome mental states. He rouses his will and strives to overcome evil unwholesome mental states that have arisen. He rouses his will and strives to produce un-arisen wholesome mental states. He rouses his will, makes an effort, stirs up energy, exerts his mind and strives to maintain wholesome mental states that have arisen and not letting them fade away, to bring them to greater growth, to the full perfection of development. What monks is Right Mindfulness? Here, monks, a monk abides contemplating body as body, ardent, clearly aware and mindful, having put aside hankering and fretting for the world; he abides contemplating feelings as feelings; he abides contemplating mind as mind; he abides contemplating mind-objects as mind-objects, ardent, clearly aware and mindful, having put aside hankering and fretting for the world. What, monks, is Right Concentration? Here a monk, detached from sense-desires, detached from unwholesome mental states, enters and remains in the first jhana, which is with thinking and pondering, born of detachment, filled with delight and joy. Then with the subsiding of thinking and pondering, by gaining inner tranquility and oneness of mind, he enters and remains in the second jhana, which is without thinking and pondering, born of concentration, filled with delight and joy. Then with the fading away of delight, remaining imperturbable, mindful and clearly aware, he experiences in himself the joy of which the Noble Ones say: "Happy is he who dwells with equanimity and mindfulness", he enters the third jhana. Then having given up pleasure and pain and with the disappearance of former gladness and sadness, he enters and remains in the fourth jhana, which is beyond pleasure and pain and purified by equanimity and mindfulness. This is called Right Concentration. And that, monks, is called the path leading to the cessation of suffering.
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So he abides contemplating mind-objects as mind-objects internally, contemplating mind-objects as mind-objects externally, contemplating mind-objects as mind-objects both internally and externally. He abides contemplating arising and cessation of phenomena in mind-objects. Or else, mindfulness that "there are mind-objects" is present just to the extent necessary for knowledge and awareness. And he abides detached, not grasping at anything in the world.That monks, is how a monk abides contemplating mind-objects as mind-objects in respect of the Four Noble Truths.' 

Buddha concluded: 'Whoever, monks, should practice these four foundations of mindfulness for just seven years may expect one of two results: either Arahantship in this life or if there should be some substrate left they can achieve the state of a Non-Returner. Let alone seven years  if they practice for just six years . . . five years. . .four years. . .three years .. . two years. . . one year...seven month... six months...5 months... 4 months...3 months....2 months...one month... half a month may expect one of two results: either Arahantship in this life or, if there should be some substrate left, the state of a Non-Returner. There is, monks, this one way to the purification of beings, for the overcoming of sorrow and distress, for the disappearance of pain and sadness, for the gaining of the right path, for the realization of Nibbana: that is the four foundations of mindfulness"and it is for this reason that it was said.
 
After this discourse by Buddha, the monks rejoiced and were delighted at his words.

In summary, Buddha explained the foundations of mindfulness by discussing the contemplation of body, contemplation of feelings, contemplation of the mind and contemplation of mind-objects. Those who practice diligently on these foundations of mindfulness meditation will achieve the fruits of enlightenment one day when practiced correctly. 

References: 
1. www.accesstoinsight.org
2. https://suttacentral.net/
3. The long discourses of the Buddha (Bhikkhu Bodhi)