四分律比丘含注戒本 2.700

2.700

If, before the settlement of the matter is finished, he moves his foot outside the threshold, he commits a fallen offense (prāyaścittika). If one foot is inside the threshold and he makes the preparatory motion to leave but does not leave, it is a duṣkṛta. For a bhikṣuṇī, it is a prāyaścittika. As for non-offenses: if he conveyed consent; if his mouth is paralyzed; if [they] perform an invalid karman; or if leaving without conveying consent is done because detriment is being brought upon the Saṃgha, stūpa, monastery, upādhyāya, ācārya, or fellow students—it is permissible.