四分律刪繁補闕行事鈔 2.256

2.256

有緣軍中過限戒四十九。四緣：一有請緣。《多》云：開往者，為沙門果故，長養佛法故，長信敬故，又道俗相須，成就佛法故，聽往有益。二曾經二夜。三第三宿不離見聞處。四明相出犯。

Precept 49: Exceeding the limit when staying in an army with reason. Four conditions: first, having a reason for being invited. The Sarvāstivāda-vinaya-vibhāṣā says: Being permitted to go is for the sake of the fruit of śramaṇahood, for nurturing the Buddha-Dharma, for increasing faith and reverence; moreover, monastics and laypeople assist each other to accomplish the Buddha-Dharma, hence allowing one to go is beneficial. Second, having already spent two nights. Third, on the third night not leaving the range of sight and hearing. Fourth, the appearance of dawn constitutes an offense.