[852] Origin at Sāvatthī. Now at that time the group-of-six bhikkhus ate licking the hand. … "I shall not eat licking the hand": thus should the training be observed.
One should not eat licking the hand. Whichever bhikkhu, out of disrespect, eats licking the hand, incurs an offense of wrong-doing (dukkaṭa).
There is no offense: for one who acts unintentionally; for one who is unmindful; for one who does not know; for one who is ill; in emergencies; for one who is insane; for the first offender.
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.