四分律比丘含注戒本 2.609

2.609

The Buddha was in Śrāvastī. Many bhikṣus were travelling to Vaiśālī. Merchants were illegally crossing a customs barrier without paying the royal tax, and accompanied the bhikṣus as traveling companions. They were caught by the barrier guards and taken before the king, their crime punishable by death. The king and worldly people criticized and rebuked them. Bhikṣus raised the fault and reported it to the Buddha, and accordingly he laid down this precept.