四分律刪補隨機羯磨 2.182

2.182

（時有比丘來至所住處安居，忘不結，佛言：「若為安居故來，便成安居。」《律》中，為客比丘本有要期，外來託處，有忘開結，必有住人，不在通限。若本有方便，理通客、主也。）

(At one time, there was a bhikṣu who came to his dwelling place for the retreat but forgot and did not bind it. The Buddha said: "If he came for the sake of the retreat, it is thereby effected as a retreat." In the Vinaya, this was for a visiting bhikṣu who originally had an appointment and came from outside to lodge; forgetting to bind it was excused, but if there were resident monks, it is not within this general allowance. If there was prior arrangement, the principle applies equally to guest and host.)