The Buddha explains to Jīvaka the circumstances in which meat may be consumed and the demerit of slaughtering living beings for the Tathāgata or his disciples.
Jīvaka sutta - Discourse with Jīvaka
Thus have I heard — at one time, the Blessed One was dwelling in Rajagaha, in the mango grove of Jīvaka Komārabhacca.
Then Jīvaka Komārabhacca approached the Blessed One; having approached, he paid homage to the Blessed One and sat down to one side. While seated to one side, Jīvaka Komārabhacca said to the Blessed One:
"I have heard, venerable sir: 'They slaughter living beings for the ascetic Gotama; the ascetic Gotama knowingly eats meat prepared for him, thus implicating himself in the act.' Those who say, 'They slaughter living beings for the ascetic Gotama; the ascetic Gotama knowingly eats meat prepared for him, thus implicating himself in the act,' do they speak in accordance with the Blessed One's teaching, without misrepresenting him with what is not true, and explaining in accordance with the Dhamma, without finding fault in agreement with the Dhamma?"
"Jīvaka, those who say, 'They slaughter living beings for the ascetic Gotama; the ascetic Gotama knowingly eats meat prepared for him, thus implicating himself in the act' do not speak in accordance with my teaching, and they accuse me falsely with what is not true.
I declare, Jīvaka, that there are three circumstances in which meat should not be consumed: when it is seen, heard, or suspected — in these three circumstances, I declare that meat should not be consumed.
I declare, Jīvaka, that there are three circumstances in which meat may be consumed: when it is not seen, not heard, and not suspected — in these three circumstances, I declare that meat may be consumed.
Here, Jīvaka, a bhikkhu dwells depending on a certain village or town. With a mind accompanied by loving-kindness, he dwells pervading one direction, in the same way the second, in the same way the third, in the same way the fourth. Thus above, below, across, and everywhere, and to all as to himself, he dwells pervading the entire world with a mind accompanied by loving-kindness, vast, exalted, measureless, without hostility, without ill-will. Then, a householder or a householder's son comes to him and invites him for the next day's meal. If he wishes, Jīvaka, the bhikkhu accepts the invitation.
After the night has passed, in the morning, he dresses, takes his bowl and robe, and goes to the house of the one who invited him; having approached, he sits down on the prepared seat. Then, that householder or householder's son serves him with good food. He does not think: 'It is good that the householder serves me with the good food, or they will serve me again in the future with such good food' — he does not think like that. He consumes the food not attached, not infatuated, not clinging, seeing the danger, and understanding the escape.
What do you think, Jīvaka, does that bhikkhu at that time intend harm for himself, for others, or for both?"
"No, venerable sir."
"Then, Jīvaka, that bhikkhu at that time consumes blameless food, doesn't he?"
"Indeed, venerable sir. I have heard, venerable sir: 'Brahmā dwells spreading goodwill.' This, venerable sir, has been made known to me directly by the Blessed One; indeed, the Blessed One dwells spreading goodwill."
"Jīvaka, whatever lust, hatred, and delusion, whatever ill-will there might be, the Tathāgata has abandoned them, cut them off at the root, made them like a palm stump, done away with them so they are no longer subject to future arising. If you speak with this in mind, Jīvaka, I allow you to say so."
"That is precisely what I had in mind, venerable sir."
Here, Jīvaka, a bhikkhu dwells depending on a certain village or town. He dwells pervading one direction with a mind accompanied by compassion, in the same way the second, in the same way the third, in the same way the fourth. Thus above, below, across, and everywhere, and to all as to himself, he dwells pervading the entire world with a mind accompanied by compassion, vast, exalted, measureless, without hostility, without ill-will.
With a mind accompanied by empathetic joy, he dwells pervading one quarter, in the same way the second, in the same way the third, in the same way the fourth. Thus above, below, across, and everywhere, and to all as to himself, he dwells pervading the entire world with a mind accompanied by empathetic joy, vast, exalted, measureless, without hostility, without ill-will.
With a mind accompanied by equanimity, he dwells pervading one quarter, in the same way the second, in the same way the third, in the same way the fourth. Thus above, below, across, and everywhere, and to all as to himself, he dwells pervading the entire world with a mind accompanied by equanimity, vast, exalted, measureless, without hostility, without ill-will. Then, a householder or a householder's son invites him for a meal. The bhikkhu, if he likes, may accept the invitation.
After the night has passed, in the morning, he dresses, takes his bowl and robe, and goes to the house of the one who invited him; having approached, he sits down on the prepared seat. Then, that householder or householder's son serves him with good food. He does not think: 'It is good that the householder serves me with the good food, or they will serve me again in the future with such good food'—he does not think like that. He consumes the food not attached, not infatuated, not clinging, seeing the danger, and understanding the escape.
What do you think, Jīvaka, does that bhikkhu at that time intend harm for himself, for others, or for both?"
"No, venerable sir."
"Then, Jīvaka, that bhikkhu at that time consumes blameless food, doesn't he?"
"Indeed, venerable sir. I have heard, venerable sir: 'Brahmā dwells spreading equanimity.' This, venerable sir, has been made known to me directly by the Blessed One; indeed, the Blessed One dwells spreading equanimity."
"Jīvaka, whatever lust, hatred, and delusion, whatever ill-will, dissatisfaction, and hostility there might be, the Tathāgata has abandoned them, cut them off at the root, made them like a palm stump, done away with them so they are no longer subject to future arising. If you speak with this in mind, Jīvaka, I allow you to say so."
"That is precisely what I had in mind, venerable sir."
"Jīvaka, anyone who slaughters a living being for the Tathāgata or his disciple accumulates much demerit in five ways.
When that householder says: 'Go, fetch that living being for me,' by this first instance, he accumulates much demerit.
When that living being experiences pain and distress being led with a noose, by this second instance, he accumulates much demerit.
When he says: 'Slaughter that living being for me,' by this third instance, he accumulates much demerit.
When that living being experiences pain and distress during the slaughter, by this fourth instance, he accumulates much demerit.
When he presents the Tathāgata or his disciple with food that is not allowable, by this fifth instance, he accumulates much demerit.
Jīvaka, anyone who slaughters a living being for the Tathāgata or his disciple accumulates much demerit through these five ways."
When this was said, Jīvaka Komārabhacca said to the Blessed One: "Wonderful, venerable sir, marvelous, venerable sir. It is fitting, venerable sir, that bhikkhus consume food in such a blameless manner. Splendid, venerable sir, splendid... Please remember me as a lay follower who has gone to the Blessed One for refuge for life."