Some kill living beings for sacrificial purposes,
Some kill for their skins,
Some kill for their flesh,
Some for the blood, heart, liver, fat, feathers or teeth….
Some out of fear.
He who is disinclined to kill the smallest living thing,
knows what suffering is, because he who sees and understands
the real cause of his own happiness and pains, knows others' too.
And he who sees and understands
others' feelings also knows his own feelings.
This is the way one must compare oneself with others.
Knowing what is bad, he who knows it with regard to himself
knows it with regard to the world;
And he who knows it with regard to the world outside,
knows it with regard to himself.
This reciprocity between oneself and others
(one should mind).
lord mahavir - acharanga sutra - stanza 1.6.55