The yogi Milarepa left his wisdom in the form of songs, two of which specifically address the topic of killing and eating animals.
Subjugating ‘outer’ appearances, will not conquer them.
Conquer your own mind, at this very moment!
Your killing this deer will not satiate you,
Killing the five poisons within, all wishes are fulfilled!
Subjugating ‘outer’ enemies, they increase even more.
Conquering one’s ‘inner’ mindstream, there are no ‘enemies’.
—Excerpt from ‘Milarepa’s Song to Animals and the Hunter’ tr. Adele Tomlin (2020)
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May all beings be well