四分律比丘含注戒本 2.209

2.209

The Buddha was in Śrāvastī. An alms-begging bhikṣu was fully endowed with deportment. A bhikṣuṇī saw him, gave rise to wholesome thoughts, and repeatedly invited him, but the bhikṣu did not accept. Later, when the Saṃgha distributed robes, he gave a robe to the bhikṣuṇī, and she readily accepted it. People reproached the bhikṣuṇī and repeatedly spoke of it to others. The bhikṣus reported this fault to the Buddha. He rebuked [them] and instituted this rule.