四分律比丘含注戒本 2.425

2.425

(If either is blind or deaf, it is a duṣkṛta. Cases of non-offence: if in a feeding household where there is a jewel, one sits where an extended hand reaches the door; if there are two bhikṣus as companions; if there is a person of discernment or a guest in the same place, and they are not blind or deaf; or passing in front without staying; falling to the ground due to sudden illness; being held by force; or being tied up; or on account of dangers to life or celibacy—there is no offence.)