大比丘三千威儀 1.60

1.60

持戶鑰有五事：一者欲出時，常當先所披貫臂著指；二者欲閉戶，不得并持鑰，牽大戶當諦視；三者欲開戶，不得并持鑰大排戶，當徐脫之；四者著常處取持自近；五者至七日當拭去鉎持。

There are five matters regarding holding the key to a door: first, when wishing to go out, one must always first thread the string around one's arm and place it on one's finger; second, when wishing to close the door, one must not hold the key together [with the door], but must pull the main door and watch carefully; third, when wishing to open the door, one must not hold the key together [with the latch] to shove open the door roughly, but must gently release it; fourth, it should be kept in a regular place and retrieved close to oneself; fifth, every seven days one must wipe away rust and maintain it.