Majjhima Nikaya 4:98
SUJATOIdha, bhikkhave, bhikkhu paṭisaṅkhā yoniso caṇḍaṁ hatthiṁ parivajjeti, caṇḍaṁ assaṁ parivajjeti, caṇḍaṁ goṇaṁ parivajjeti, caṇḍaṁ kukkuraṁ parivajjeti, ahiṁ khāṇuṁ kaṇṭakaṭṭhānaṁ sobbhaṁ papātaṁ candanikaṁ oḷigallaṁ.
Take a mendicant who, reflecting rationally, avoids a wild elephant, a wild horse, a wild ox, a wild dog, a snake, a stump, thorny ground, a pit, a cliff, a swamp, and a sewer.