​MN 79 Culasakuludayi Sutta: The Shorter Discourse to Sakuludayin 

Thus have i heard. 

On one occasion the Blessed One was living at Rajagaha in the Bamboo Grove, the Squirrels' Sanctuary. Now on that occasion the wanderer Sakuludayin was staying in the Peacocks' Sanctuary, the wanderers' park, with a large assembly of wanderers. In the morning, the Blessed One dressed, and taking his bowl and outer robe, went to Rajagaha for alms. Then he thought: "It is still too early to wander for alms in Rajagaha. Suppose I went to the wanderer Sakuludayin in the Peacocks' Sanctuary." Then the Blessed One went to the Peacocks' Sanctuary, the wanderers' park.

Now on that occasion the wanderer Sakuludayin was seated with a large assembly of wanderers who were making an uproar...(as Sutta 77)..
The blessed one asked : "For what discussion are you sitting together here now, Udayin? And what was your discussion that was interrupted?"
Udayin: "Venerable sir, let be the discussion for which we are now sitting together here. The Blessed One can well hear about it later. Venerable sir, when I do not come to this assembly, then it sits talking many kinds of pointless talk. But when I have come to this assembly, then it sits looking up to me, thinking: 'Let us hear the Dhamma that the recluse Udayin expounds.' However, when the Blessed One comes, then both I and this assembly sit looking up to the Blessed One, thinking: 'Let us hear the Dhamma that the Blessed One expounds.'"

Buddha: "Then, Udayin, suggest something that I should speak about."
Udayin : "Venerable sir, in recent days there was one claiming to be omniscient and all-seeing, to have complete knowledge and vision thus: 'Whether I am walking or standing or sleeping or awake, knowledge and vision are continuously and uninterruptedly present to me.' When I asked him a question about the past, he prevaricated, led the talk aside, and showed anger, hate, and bitterness. Then I remembered the Blessed One thus: 'Ah, surely it is the Blessed One, surely it is the Sublime One who is skilled in these things.'"

Buddha: "But, Udayin, who was it that claimed to be omniscient and all-seeing...yet when asked a question by you about the past, prevaricated, led the talk aside, and showed anger, hate, and bitterness?"
Udayin: "It was the Nigantha Nataputta, venerable sir."
Buddha: "Udayin, if someone should recollect his manifold past lives with their aspects and particulars, then either he might ask me a question about the past or I might ask him a question about the past, and he might satisfy my mind with his answer to my question or I might satisfy his mind with my answer to his question. If someone with the divine eye, which is purified and surpasses the human, should see beings passing away and reappearing, inferior and superior, fair and ugly, fortunate and unfortunate... and understand how beings pass on according to their actions, then either he might ask me a question about the future or I might ask him a question about the future, and he might satisfy my mind with his answer to my question or I might satisfy his mind with my answer to his question. But let be the past, Udayin, let be the future. I shall teach you the Dhamma: When this exists, that comes to be; with the arising of this, that arises. When this does not exist, that does not come to be; with the cessation of this, that ceases."

Udayin: "Venerable sir, I cannot even recollect with their aspects and particulars all that I have experienced within this present existence, so how should I recollect my manifold past lives, ...with their aspects and particulars, as the Blessed One does? And I cannot now even see a mud-goblin, so how should I with the divine eye, which is purified and surpasses the human, see beings passing away and reappearing, inferior and superior, fair and ugly, fortunate and unfortunate...and understand how beings pass on according to their actions, as the Blessed One does? But, venerable sir, when the Blessed One told me: 'But let be the past, Udayin, let be the future. I shall teach you the Dhamma: When this exists, that comes to be; with the arising of this, that arises. When this does not exist, that does not come to be; with the cessation of this, that ceases' - that is even more unclear to me. Perhaps, venerable sir, I might satisfy the Blessed One's mind by answering a question about our own teachers' doctrine."
​ "Well, Udayin, what is taught in your own teachers' doctrine?"
Udayin: "Venerable sir, it is taught that in our own teachers' doctrine: 'This is the perfect splendor, this is the perfect splendor!'"
Budda: "But, Udayin, what is that perfect splendor?"
Udayin: "Venerable sir, that splendor is the perfect splendor which is unsurpassed by any other splendor higher or more sublime."
Buddha: "But, Udayin, what is that splendor which is unsurpassed by any other splendor higher or more sublime?"

​Udayin: "Venerable sir, that splendor is the perfect splendor which is unsurpassed by any other splendor higher or more sublime."
Buddha: "Udayin, you might continue for a long time in this way. You say: 'Venerable sir, that splendor is the perfect splendor which is unsurpassed by any other splendor higher or more sublime,' yet you do not indicate what that splendor is. Suppose a man were to say: 'I am in love with the most beautiful girl in this country.' Then they would ask him: 'Good man, that most beautiful girl in this country with whom you are in love - do you know whether she is from the noble class or the brahmin class or the merchant class or the worker class?' and he would reply: 'No.' Then they would ask him: 'Good man, that most beautiful girl in this country with whom you are in love do you know her name and clan?...Whether she is tall or short or of middle height?...Whether she is dark or brown or golden-skinned?... What village or town or city she lives in?' and he would reply: 'No.' And then they would ask him: 'Good man, do you then love a girl you have never known or seen?' and he would reply: 'Yes.' What do you think, Udayin, that being so, would not that man's talk amount to nonsense?"
Udayin: "Surely, venerable sir, that being so, that man's talk would amount to nonsense."
Buddha: "But in the same way, Udayin, you say thus: 'That splendor is the perfect splendor which is unsurpassed by any other splendor higher or more sublime,' yet you do not indicate ​what that splendor is."
Udayin: "Venerable sir, just as a beautiful beryl gem of purest water, eight-faceted, well cut, lying on red brocade, glows, radiates, and shines, of such splendor is the self [surviving] unimpaired after death."

Buddha: "What do you think, Udayin? This beautiful beryl gem of purest water which glows, radiates, and shines, or a glowworm in the thick darkness of the night - of these two, which gives off the splendor that is more excellent and sublime?"
Udayin: "The glowworm in the thick darkness of the night, venerable sir."
Buddha: "What do you think, Udayin? This glowworm in the thick darkness of the night or an oil-lamp in the thick darkness of the night - of these two, which gives off the splendor that is more excellent and sublime?"
Udayin: "The oil-lamp, venerable sir."
Buddha: "What do you think, Udayin? This oil-lamp in the thick darkness of the night or a great bonfire in the thick darkness of the night - of these two, which gives off the splendor that is more excellent and sublime?"
Udayin: "The great bonfire, venerable sir."

Buddha:  "What do you think, Udayin? This great bonfire in the thick darkness of the night or the morning star towards dawn in a clear cloudless sky - of these two, which gives off the splendor that is more excellent and sublime?"
Udayin: "The morning star towards dawn in a clear cloudless sky, venerable sir."
Buddha: "What do you think, Udayin? The morning star towards dawn in a clear cloudless sky or the full moon at midnight in a clear cloudless sky on the Uposatha day of the fifteenth - of these two, which gives off the splendor that is more excellent and sublime?"
Udayin: "The full moon at midnight in a clear cloudless sky on the Uposatha day of the fifteenth, venerable sir." Buddha: "What do you think, Udayin? The full moon at midnight in a clear cloudless sky on the Uposatha day of the fifteenth, or the full disk of the sun at midday in a clear cloudless sky in autumn in the last month of the rainy season - of these two, which gives off the splendor that is more excellent and sublime?"
Udayin: "The full disk of the sun at midday in a clear cloudless sky in autumn in the last month of the rainy season, venerable sir."

Buddha: "Beyond this, Udayin, I know of very many gods whose splendor the radiance of the sun and moon does not match, yet I do not say that there is no other splendor higher or more sublime than that splendor. But you, Udayin, say of that splendor which is lower and meaner than a glowworm's: 'This is the perfect splendor,' yet you do not indicate what that splendor is." 
 Udayin: "The Blessed One has terminated the discussion; the Sublime One has terminated the discussion."
Buddha: "But, Udayin, why do you say that?"
Udayin: "Venerable sir, it is taught in our own teachers' doctrine: 'This is the perfect splendor, this is the perfect splendor.' But on being pressed and questioned and cross-questioned about our own teachers' doctrine by the Blessed One, we are found empty, hollow, and mistaken."

Buddha: "How is it, Udayin, is there an entirely pleasant world? Is there a practical way to realize an entirely pleasant world?"
Udayin: "Venerable sir, it is taught in our own teachers' doctrine: 'There is an entirely pleasant world; there is a practical way to realize an entirely pleasant world.'"
Buddha: "But, Udayin, what is that practical way to realize an entirely pleasant world?"
Udayin: "Here, venerable sir, abandoning the killing of living beings, abandoning the taking of what is not given, abandoning misconduct in sensual pleasures, abandoning false speech, he abstains from false speech; or else he undertakes and practises some kind of asceticism. This is the practical way to realize an entirely pleasant world."
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Buddha: "What do you think, Udayin? On an occasion when he abandons the killing of living beings and abstains from killing living beings, does his self then feel only pleasure or both pleasure and pain?"
Udayin: "Both pleasure and pain, venerable sir."
Buddha: "What do you think, Udayin? On an occasion when he abandons the taking of what is not given...when he abandons misconduct in sensual pleasures ... when he abandons false speech and abstains from false speech, does his self then feel only pleasure or both pleasure and pain?"
Udayin: "Both pleasure and pain, venerable sir."
Buddha: "What do you think, Udayin? On an occasion when he under takes and practices some kind of asceticism, does his self then feel only pleasure or both pleasure and pain?"
Udayin: "Both pleasure and pain, venerable sir."
Buddha: "What do you think, Udayin? Does the realization of an entirely pleasant world come about by following a way of mixed pleasure and pain?" 
​Udayin: "The Blessed One has terminated the discussion; the Sublime One has terminated the discussion."
Buddha: "But, Udayin, why do you say that?"
Udayin: "Venerable sir, it is taught in our own teachers' doctrine: "There is an entirely pleasant world; there is a practical way to realize an entirely pleasant world.' But on being pressed and questioned and cross-questioned about our own teachers' doctrine by the Blessed One, we are found empty, hollow, and mistaken. But how is it, venerable sir, is there an entirely pleasant world? Is there a practical way to realize an entirely pleasant world?"

Buddha: "There is an entirely pleasant world, Udayin; there is a practical way to realize an entirely pleasant world." Here, Udayin, quite secluded from sensual pleasures, secluded from unwholesome states, a bhikkhu enters upon and abides in the first jhana...With the stilling of applied and sustained thought, he enters upon and abides in the second jhana...in the third jhana...This is the practical way to realize an entirely pleasant world."
Udayin: "Venerable sir, that is not the practical way to realize an entirely pleasant world; at that point an entirely pleasant world has already been realized."
Buddha: "Udayin, at that point an entirely pleasant world has not yet been realized; that is only the practical way to realize an entirely pleasant world."

When this was said, the wanderer Sakuludayin's assembly made an uproar, saying very loudly and noisily: "We are lost along with our own teachers' doctrines! We are lost along with our own teachers' doctrines! We know nothing higher than that!" 

Then the wanderer Sakuludayin quieted those wanderers and asked the Blessed One: "Venerable sir, at what point is an entirely pleasant world realized?"
​Buddha: "Here, Udayin, with the abandoning of pleasure and pain, and with the previous disappearance of joy and grief, a bhikkhu enters upon and abides in the fourth jhana, which has neither pain-nor-pleasure and purity of mindfulness due to equanimity. He dwells with those deities who have arisen in an entirely pleasant world and he talks with them and enters into conversation with them. It is at this point that an entirely pleasant world has been realised."

Udayin: "Venerable sir, surely it is for the sake of realizing that entirely pleasant world that bhikkhus lead the holy life under the Blessed One."
Buddha: "It is not for the sake of realizing that entirely pleasant world that bhikkhus lead the holy life under me. There are other states, Udayin, higher and more sublime than that and it is for the sake of realizing them that bhikkhus lead the holy life under me."
Udayin: "What are those higher and more sublime states, venerable sir, for the sake of realizing which bhikkhus lead the holy life under the Blessed One?"

Buddha: "Here, Udayin, a Tathagata appears in the world, accomplished, fully enlightened...(as Sutta 51)...he purifies his mind from doubt. Having thus abandoned these five hindrances, imperfections of the mind that weaken wisdom, quite secluded from sensual pleasures, secluded from unwholesome states, a bhikkhu enters upon and abides in the first jhana...This, Udayin, is a higher and more sublime state for the sake of realising which bhikkhus lead the holy life under me."

"Again, with the stilling of applied and sustained thought, a bhikkhu enters upon and abides in the second jhana...the third jhana...the fourth jhana. This too, Udayin, is a higher and more sublime state for the sake of realizing which bhikkhus lead the holy life under me."

"When his concentrated mind is thus purified, bright, unblemished, rid of imperfection, steady, and attained to imperturbability, he directs it to knowledge of the recollection of past lives. He recollects his manifold past lives...(as Sutta 51)...Thus with their ​aspects and particulars he recollects his manifold past lives. This too, Udayin, is a higher and more sublime state for the sake of realizing which bhikkhus lead the holy life under me. "
"When his concentrated mind is thus purified, bright, unblemished, rid of imperfection and attained to imperturbability, he directs it to knowledge of the passing away and reappearance of beings...(as Sutta 51)... Thus with the divine eye, which is purified and surpasses the human, he sees beings passing away and reappearing, inferior and superior, fair and ugly, fortunate and unfortunate, and he understands how beings pass on according to their actions. This too, Udayin, is a higher and more sublime state for the sake of realizing which bhikkhus lead the holy life under me."

"When his concentrated mind is thus purified, bright, unblemished, rid of imperfection,steady, and attained to imperturbability, he directs it to knowledge of the destruction of the taints. He understands as it actually is : 'This is suffering'...(as Sutta 51)],..He understands as it actually is: 'This is the way leading to the cessation of the taints.' "
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"When he knows and sees thus, his mind is liberated from the taint of sensual desire, from the taint of being, and from the taint of ignorance. When it is liberated there comes the knowledge: 'It is liberated.' He understands: 'Birth is destroyed, the holy life has been lived, what had to be done has been done, there is no more coming to any state of being.' These, Udayin, are those higher and more sublime states for the sake of realizing which bhikkhus lead the holy life under me."

When this was said, the wanderer Sakuludayin said to the Blessed One: "Magnificent, venerable sir! Magnificent, venerable sir! The Blessed One has made the Dhamma clear in many ways, as though he were turning upright what had been overthrown, revealing what was hidden, showing the way to one who was lost, or holding up a lamp in the dark for those with eyesight to see forms. I go to the Blessed One for refuge and to the Dhamma and to the Sangha of bhikkhus. I would receive the going forth under the Blessed One, venerable sir, I would receive the full admission."
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​When this was said, the wanderer Sakuludayin's assembly addressed him thus: "Do not lead the holy life under the recluse Gotama, Master Udayin. Having been a teacher, Master Udayin, do not live as a pupil. For Master Udayin to do so would be as if a water jug were to become a pitcher. Do not lead the holy life under the recluse Gotama, Master Udayin. Having been a teacher, Master Udayin, do not live as a pupil." 
That is how the wanderer Sakuludayin's assembly obstructed him from leading the holy life under the Blessed One. 
In summary, Buddha met an Wanderer Sakuludayi and his followers, the Buddha told him:" I shall teach you the Dhamma: When this exists, that comes to be; with the arising of this, that arises. When this does not exist, that does not come to be; with the cessation of this, that ceases."

Buddha asked Sakuludayi what was his teacher's doctrine and the latter replied "This is the perfect splendor" however he could not explain what is splendor. The Buddha said the doctrine of a wanderer is a folly using the simile of "the most beautiful girl in the country"  in which one has not even met the most beautiful girl but yet claimed they are in love with her. ​

Buddha then asked Sakuludayi's concept of  an entirely pleasant world according to his teachings. He corrected Sakuludayi's concept by elaborating on the practical way to realize an entirely pleasant world: attaining jhana meditative states, overcoming the five hindrances, attainment of three knowledges and liberation from taints. 
References: 
1. www.accesstoinsight.org
2. https://suttacentral.net/
3. The middle length discourses of the Buddha (Bhikkhu Bodhi)