For innumerable reasons, Mahamati, the Bodhisattva, whose nature is compassion, is not to eat any meat; I will explain them: Mahamati, in this long course of transmigration here, there is not one living being that, having assumed the form of a living being, has not been your mother, or father, or brother, or sister, or son, or daughter, or the one or the other, in various degrees of kinship; and when acquiring another form of life may life as a beast, as a domestic animal, as a bird, or as a womb-born, or as something standing in some relationship to you; [this being so] how can the Bodhisattva-Mahasattva who desires to approach all living beings as if they were himself and to practise the Buddha-truths, eat the flesh of any living being that is of the same nature as himself? Even, Mahamati, the Rakshasa, listening to the Tathagata’s discourse on the highest essence of the Dharma, attained the notion of protecting [Buddhism], and, feeling pity, refrains from eating flesh; how much more those who love the Dharma! Thus, Mahamati, wherever there is the evolution of living beings, let people cherish the thought of kinship with them, and, thinking that all beings are to be loved as if they were an only child, let them refrain from eating meat. So with Bodhisattvas whose nature is compassion, [the eating of meat] is to be avoided by him. Even in exceptional cases, it is not [compassionate] of a Bodhisattva of good standing to eat meat. The flesh of a dog, an ass, a buffalo, a horse, a bull or a man, or any other being, Mahamati, that is not generally eaten by people, is sold on the roadside as mutton for the sake of money; and therefore, Mahamati, the Bodhisattva should not eat meat.

For the sake of love of purity, Mahamati, the Bodhisattva should refrain from eating flesh which is born of semen, blood, etc. For fear of causing terror to living beings, Mahamati, let the Bodhisattva who is disciplining himself to obtain compassion, refrain from eating flesh. To illustrate, Mahamati: When a dog sees, even from a distance, a hunter, a pariah, a fisherman, etc, whose desires are for meat-eating, he is terrified with fear, thinking, “They are death-dealers, they will even kill me.” In the same way, Mahamati, even those minute animals that are living in the air, on earth, and in water, seeing meat-eaters at a distance, will perceive in them, by their keen sense of smell, the odour of the Rakshasa and will run away from such people as quickly as possible; for they are to them the threat of death. For this reason, Mahamati, let the Bodhisattva, who is disciplining himself, to abide in great compassion, because of its terrifying living beings, refrain from eating meat. The food of the wise, Mahamati, is what is eaten by the Rishis; it does not consist of meat and blood. Therefore, Mahamati, let the Bodhisattva refrain from eating meat.

In order to guard the minds of all people, Mahamati, let the Bodhisattva whose nature is holy and who is desirous of avoiding censure on the teaching of the Buddha, refrain from eating meat. For instance, Mahamati, there are some in the world who speak ill of the teaching of the Buddha; who say: “Why are those who are living the life of a Sramana or a Brahmin rejecting such food as was enjoyed by the ancient Rishis, and eating like the carniverous animals, living in the air, on earth, or in the water? Why do they go wandering about in the world thoroughly terrifying living beings, disregarding the life of a Sramana and destroying the vow of a Brahmin? There is no Dharma, no discipline, in them.” There are many such adverse-minded people who thus speak ill of the teaching of the Buddha. For this reason, Mahamati, in order to guard the minds of all people, let the Bodhisattva whose nature is full of pity and who is desirous of avoiding censure on the teaching of the Buddha, refrain from eating meat.

Such as these, Mahamati, are the evils of meat-eating; how much more numerous [evil] qualities that are born of the perverted minds of those devoted to meat-eating. And, Mahamati, the ignorant and simple-minded are not aware of all this and other evils and merits [in connection with meat-eating]. I tell you, Mahamati, that seeing these evils and merits the Bodhisattva whose nature is pity should eat no meat.

If, Mahamati, meat is not eaten by anybody for any reason, there will be no destroyer of life. Mahamati, in the majority of cases the slaughter of innocent living beings is done for pride and very rarely for other causes. Though nothing special may be said of eating flesh of living creatures such as animals and birds, alas, Mahamati, that one addicted to the taste of meat taste should eat human flesh! Mahamati, in most cases nets and other devices are prepared in various places by people who have lost their sense on account of their appetite for meat taste, and thereby many innocent victims are destroyed for the sake of the price they bring in. There are even some, Mahamati, who are like Rakshasas hard-hearted and used to practising cruelties, who, being so devoid of compassion, would now and then look at living beings as meant for food and destruction – no compassion is awakened in them.

It is not true, Mahamati, that meat is proper food and permissible for the Sravaka when the victim was not killed by himself, when he did not order others to kill it, when it was not specially meant for him. Again, Mahamati, there may be some unwitting people in the future time, who, beginning to lead the homeless life according to my teachings, are acknowledged as sons of the Sakya, and carry the Kashaya robe about them as a badge, but who are in thought evilly affected by erroneous reasonings. They may talk about various discriminations they make in their moral discipline, being addicted to the view of an immortal soul. Being under the influence of the thirst for meat-taste, they will string together in various ways some sophistic arguments to defend meat-eating. They think they are giving me an unprecedented calumny when they discriminate and talk about facts that are capable of various interpretations. Imagining that this fact allows this interpretation, they conclude that the Blessed One permits meat as proper food, and that this is mentioned among permitted foods and that probably the Tathagata himself partook of it. But, Mahamati, nowhere in the sutras is meat permitted as something enjoyable, nor is it referred to as proper among the foods prescribed.

If however, Mahamati, I had mind to permit meat eating, or if I said it was proper for the Sravakas to eat meat, I would not have forbidden, I would not forbid, all meat-eating for these Yogins, the sons and daughters of good family, who, wishing to cherish the idea that all beings are to them like and only child, are possessed of compassion, practise contemplation, mortification ,and are on their way to the Mahayana. And, Mahamati, the interdiction not to eat meat is here given to all sons and daughters of good family, whether they are cemetery-ascetics or forest-ascetics, or Yogins who are practising the exercises, if they wish the Dharma and are on their way to the mastery of any vehicle, and being possessed of compassion, conceive the idea of regarding all beings as an only child, in order to accomplish the end of their discipline…. Further, a tenfold prohibition is given as regards the flesh of animals found dead by themselves. All meat-eating in any form, in any manner, and in any place, is unconditionally and once for all, prohibited for all.

Thus, Mahamati, meat-eating I have not permitted to anyone, I do not permit, I will not permit.

http://www.drba.org/dharma/veggie/lankavatara.asp