What is the purpose of becoming vegetarian?
Very obvious: Great Compassion! The Buddha says eating meat
destroys the very root of compassion, therefore Bodhisattva
practitioners whom compassion is so important, must avoid eating
meat.
Surangama Sutra (Mahayana)
In the Chapter entitled "The enlightenment of others" and the
section Prohibition against Killing, page 154. The Buddha
said:
"If a man can (control) his body and mind and thereby refrains from
eating animal flesh and wearing animal products, I say he will
really be liberated."
Also from the Surangama Sutra:
"The reason for practicing dhyana and seeking to attain Samadhi is
to escape from the suffering of life, but in seeking to escape from
the suffering ourselves why should we inflict it upon others?
Unless you can so control your minds that even the thought of
brutal unkindness and killing is abhorrent, you will never be able
to escape from the bondage of the worlds life
After my Parinirvana
in the last kalpa different kinds of ghosts will be encountered
everywhere deceiving people and teaching them that they can eat
meat and still attain enlightenment
How can a bhikshu, who hopes
to become a deliverer of others, himself be living on the flesh of
other sentient beings?"
Brahmajala Sutra, (What the Teaching is Not), from the Pali Canon;
"Long Discourses of the Buddha", Sutta 1: Translation by Maurice
Walshe pages 69 and 70.
"Whereas some ascetics and Brahmins, feeding on the food of the
faithful, remain addicted to the enjoyment of stored-up goods such
as food, drink, clothing, carriages, beds, perfumes and meat, the
ascetic Gotama refrains from such enjoyment."
Lankavatara Sutra (Mahayana) translated from Sanskrit by D. T.
Suzuki. This Sutra was a discussion of the fundamental concepts of
Mahayana Buddhism. Chapter Eight is entirely devoted to the
prohibition of meat eating.
"The Blessed One said this to him: For innumerable reasons,
Mahamati, the Boddhisattva, whose nature is compassion, is not to
eat any meat."
"Now, Mahamati, the food I have permitted (my disciples to take) is
gratifying to all wise people but is avoided by the unwise; it is
productive of many merits, it keeps away many evils; and it has
been prescribed by the ancient Rishis. It comprises rice, barley,
wheat, kidney beans, beans, lentils, etc., clarified butter, oil,
honey, molasses, treacle, sugar cane, coarse sugar, etc.; food
prepared with these is proper food."
"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 slaughtering of innocent living beings is done for pride and
very rarely for other causes."
"It is not true, Mahamati, that meat is proper food and permissible
for the Sravaka ( a hearer, hence a pupil or beginner) 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."
Scripture of Brahmas Net translated from the Chinese by Rev.
Hubert Nearman with Rev. Master Jiyu-Kennett and Rev. Daizui
MacPhillamy as consultants and editors. Page 138.
Third Less Grave Precept:
On eating meat.
"Disciples of the Buddha, should you willingly and knowingly eat
flesh, you defile yourself by acting contrary to this less grave
Precept. Pray, let us not eat any flesh or meat whatsoever coming
from living beings."