四分律刪補隨機羯磨 1.419

1.419

「汝一切不得犯婬、作不淨行。若比丘犯不淨行，受婬欲法，乃至共畜生，非沙門，非釋子。爾時世尊與說譬喻：『猶如有人截其頭，終不能還活，比丘亦如是，犯波羅夷法已，不能還成比丘行。』汝是中盡形壽不得作，能持不？」

"You must under no circumstances commit sexual misconduct or engage in impure conduct. If a bhikṣu commits impure conduct, practicing carnal desire, down to doing so with an animal, he is not a śramaṇa, not a son of the Śākya. At that time, the World-Honoured One spoke a parable for them: 'Just as when a person has his head severed, he can never again be revived, so too is a bhikṣu: having committed a pārājika dharma, he can never again achieve the conduct of a bhikṣu.' In this matter, you must not do so as long as your life lasts; are you able to uphold this?"