The Long Āgama Sūtra 25.32

25.32

迦葉言：「若有異學欲來入佛法中修梵行者，當留四月觀察，稱可眾意，然後當得出家受戒。我今能於佛法中四歲觀察，稱可眾意，然後乃出家受戒。」

Kāśyapa said, “If someone from another training wishes to enter the Buddha’s teaching and cultivate the religious life, they will wait to be observed for four months to assess their many ideas. Afterward, they can leave home and receive the Saṅgha’s assent. Now, I would be willing to wait for four years of observation to enter the Buddha’s teaching to receive the Saṅgha’s assent. Afterward, I’ll leave home and accept the precepts.”