大比丘三千威儀 2.27

2.27

There are further five matters: first, one must not wipe the face and eyes with one's hand; second, once the left hand is soiled, it must not approach the right hand; third, if the hand is soiled, one must not fetch water for the pātra; fourth, one must not adjust the kāṣāya with a soiled hand; fifth, one must not take the hand-cloth to wipe greasy hands.