Vinayasamgraha 3.4

3.4

爾時薄伽梵在佛栗氏國，時諸苾芻聞佛說不淨觀，既修習已，於膿血身深生厭離，便求鹿杖外道沙門令其斷命，并自相殺。凡為殺者，並由不忍事及不忍煩惱，斷他命根，制斯學處。

At that time, the Bhagavat was staying in the country of the Vṛjis. At that time, the bhikṣus heard the Buddha teach the contemplation of impurity. Having practiced it, they developed deep revulsion toward this body of pus and blood, and thereupon sought out the non-Buddhist ascetic with a deer-staff to have him take their lives, and also killed one another. Because all who kill cut off another's life-faculty through inability to endure circumstances and inability to endure defilements, [the Buddha] formulated this training rule: