On meat eating and uncleanliness by Buddha Shakyamuni:
"Taking life, beating, cutting, binding, stealing, lying, fraud, deceit, pretence at knowledge, adultery; this is uncleanliness and not the eating of flesh.
When men are rough and harsh, back biting, treacherous, without compassion, haughty, ungenerous and do not give anything to anybody; this is uncleanliness and not the eating of flesh.
Anger, pride, obstinacy, antagonism, hypocrisy, envy, ostentation, pride of opinion, intercourse with the unrighteous; this is uncleanliness and not the eating of flesh.
When men are of bad morals, refuse to pay their debts, slanderers, deceitful in their dealings, pretenders, when the vilest of men commit foul deeds; this is uncleanliness and not the eating of flesh.
When men attack living beings either because of greed or hostility, and are always bent upon evil, they go to darkness after death and fall headlong into hell; this is uncleanliness and not the eating of flesh.
Jivaka, I have declared that one should not make use of meat if it has been seen, heard or suspected to have been killed on purpose for a monk. I allow the monks meat that is quite pure in three respects: if it is not seen, heard or suspected to have been killed on purpose for a monk."
(S. Amagandha Sutta)