四分律比丘含注戒本 1.378

1.378

(The Buddha was in Śrāvastī. Kālodayin and the bhikṣuṇī Thullanandā were both handsome in appearance and mutually infatuated. While seated, he had an emission of impurity which soiled his antarvāsaka, and he had the bhikṣuṇī wash it. Bhikṣus reported the fault to the Buddha, who thereupon rebuked him and formulated the precept.)