​MN 55 Jivaka Sutta: To Jivaka 

 Thus have i heard. 

On one occasion the Blessed One was living at Rajagaha in the Mango Grove of Jivaka Komarabhacca. Then Jivaka Komarabhacca went to the Blessed One, and after paying homage to him, he sat down at one side and said to the Blessed One: "Venerable sir, I have heard this: 'They slaughter living beings for the recluse Gotama; the recluse Gotama knowingly eats meat prepared for him from animals killed for his sake.' Venerable sir, do those who speak thus say what has been said by the Blessed One, and not misrepresent him with what is contrary to fact? Do they explain in accordance with the Dhamma in such a way that nothing which provides a ground for censure can be legitimately deduced from their assertions?"

Buddha: "Jivaka, those who speak thus do not say what has been said by me, but misrepresent me with what-is untrue and contrary to fact. Jivaka, I say that there are three instances in which meat should not be eaten: when it is seen, heard, or suspected that the living being has been slaughtered for the bhikkhu. I say that meat should not be eaten in these three instances. I say that there are three instances in which meat may be eaten: when it is not seen, not heard, and not suspected that the living being has been slaughtered for the bhikkhu, I say that meat may be eaten in these three instances."

Buddha: "Here Jivaka, some bhikkhu lives in dependence upon a certain village or town. He abides pervading one quarter with a mind imbued with loving-kindness, likewise the second, likewise the third, likewise the fourth; so  everywhere, and to all as to himself, he abides pervading the all-encompassing world with a mind imbued with loving-kindness abundant, immeasurable, without hostility and without ill will. Then a householder or a householder's son comes to him and invites him for the next day's meal. The bhikkhu accepts, if he likes. Then the next morning he dresses, and taking his bowl and outer robe, goes to the house of that householder or householder's son and sits down on a seat made ready. Then the householder or householder's son serves him with good alms food. He does not think: 'How good that the householder or householder's son serves me with good alms food! If only a householder or householder's son might serve me with such good alms food in the future!' He does not think thus. He just eats that alms food without attachment to it, infatuated with it, and utterly committed to it, seeing the danger in it and understanding the escape from it. What do you think, Jivaka? Would that bhikkhu on such an occasion choose for his own affliction, or for another's affliction, or for the affliction of both?"
Jivaka: "No, venerable sir."
Buddha: "Does not that bhikkhu sustain himself with blameless food on that occasion?"
"Yes, venerable sir. I have heard this, venerable sir: 'Brahma abides in loving-kindness.' Venerable sir, the Blessed One is my visible witness to that; for the Blessed One abides in loving-kindness."
Buddha: "Jivaka, any lust, any hate, any delusion whereby ill will might arise have been abandoned by the Tathagata, cut off at the root, done away with so that they are no longer subject to future arising. If what you said referred to that, then I allow it to you."
Jivaka: "Venerable sir, what I said referred to precisely that."

Buddha: "Here, Jivaka, a bhikkhu lives in dependence upon a certain village or town. He abides pervading one quarter with a mind imbued with compassion...with a mind imbued with appreciative joy...with a mind imbued with equanimity, likewise the second, likewise the third, likewise the fourth; so everywhere, and to all as to himself, he abides pervading the all-encompassing world with a mind imbued with equanimity, abundant, immeasurable, without hostility and without ill will. Then a householder or a householder's son comes to him and invites him for the next day's meal. The bhikkhu accepts, if he likes...What do you think, Jivaka? Would that bhikkhu on such an occasion choose for his own affliction, or for another's affliction, or for the affliction of both?"
Jivaka: "No, venerable sir."
Buddha:"Does not that bhikkhu sustain himself with blameless food on that occasion?" 
​Jivaka: "Yes, venerable sir. I have heard this, venerable sir: 'Brahma abides in equanimity.' Venerable sir, the Blessed One is my visible witness to that; for the Blessed One abides in equanimity."
Buddha: "Jivaka, any lust, any hate, any delusion whereby cruelty or discontent or aversion might arise have been abandoned by the Tathagata, cut off at the root, made like a palm stump, done away with so that they are no longer subject to future arising. If what you said referred to that, then I allow it to you." 
Jivaka: "Venerable sir, what I said referred to precisely that."

Buddha: "If anyone slaughters a living being for the Tathagata or his disciple, he lays up much demerit in five instances:

1. When he says: 'Go and fetch that living being,' this is the first instance in which he lays up much demerit.
2. When that living being experiences pain and grief on being led along with a neck-halter, this is the second instance in which he lays up much demerit.
3. When he says: 'Go and slaughter that living being,' this is the third instance in which he lays up much demerit.
4. When that living being experiences pain and grief on being slaughtered, this is the fourth instance in which he lays up much demerit.
5. When he provides the Tathagata or his disciple with food that is not permissible, this is the fifth instance in which he lays up much demerit.
Anyone who slaughters a living being for the Tathagata or his disciple lays up much demerit in these five instances."

When this was said, Jivaka Komarabhacca said to the Blessed One: "It is wonderful, venerable sir, it is marvellous! The bhikkhus sustain themselves with permissible food. The bhikkhus sustain themselves with blameless food. Magnificent, venerable sir! Magnificent, venerable sir!...From today let the Blessed One remember me as a lay follower who has gone to him for refuge for life."
 In summary, Jivaka told buddha that there were accusations of living beings been killed for the bhikkhus to consume. The Buddha explains the regulations he has laid down concerning meat-eating and defends his disciples against unjust accusations. ​The Buddha refutes the accusation that he allows the eating of the flesh of animals killed specifically for him and he explains the parameters that allow the eating of meat. 

Buddha: "Jivaka, those who speak thus do not say what has been said by me, but misrepresent me with what-is untrue and contrary to fact. Jivaka, I say that there are three instances in which meat should not be eaten: when it is seen, heard, or suspected that the living being has been slaughtered for the bhikkhu. I say that meat should not be eaten in these three instances. I say that there are three instances in which meat may be eaten: when it is not seen, not heard, and not suspected that the living being has been slaughtered for the bhikkhu, I say that meat may be eaten in these three instances."

At the end of the sutta Buddha also mentioned: "If anyone slaughters a living being for the Tathagata or his disciple, he lays up much demerit in five instances. "
References: 
1. www.accesstoinsight.org
2. https://suttacentral.net/
3. The middle length discourses of the Buddha (Bhikkhu Bodhi)