[128] Now at that time a certain young man (māṇavaka) deprived his mother of life. He was troubled, ashamed, and disgusted by that evil deed. Then it occurred to that young man: "By what means might I make an escape from this evil deed?" Then it occurred to that young man: "These ascetics, sons of the Sakyan, are practicers of the Dhamma, practicers of calm, livers of the holy life, speakers of truth, virtuous, and of good character. If I were to go forth among the ascetics, sons of the Sakyan, in this way I might make an escape from this evil deed." Then that young man approached the bhikkhus and requested the going forth. The bhikkhus said this to the Venerable Upāli: "Friend Upāli, previously a nāga went forth among the bhikkhus in the guise of a young man. Come, friend Upāli, examine this young man." Then that young man, being examined by the Venerable Upāli, disclosed the matter. The Venerable Upāli informed the bhikkhus of the matter. The bhikkhus informed the Blessed One of the matter.
"Bhikkhus, a matricide (mātughātaka), if not yet fully ordained, should not be given the full ordination; if fully ordained, he should be expelled."
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.