And what, bhikkhus, is the training of a Holy One? 

He teaches Dhamma that’s good in the beginning, good in the middle, and good in the end, meaningful and well-phrased. And he reveals a spiritual practice that’s entirely full and pure. This is the training of a Holy One. 

Katamo ca, bhikkhave, sugatavinayo?

So dhammaṃ deseti ādikalyāṇaṃ majjhekalyāṇaṃ pariyosānakalyāṇaṃ sātthaṃ sabyañjanaṃ, kevalaparipuṇṇaṃ parisuddhaṃ brahmacariyaṃ pakāseti. Ayaṃ, bhikkhave, sugatavinayo.

Source: Sugatavinaya Sutta AN 4.160  AN ii 147