शमो दमस्तपः शौचं क्षान्तिरार्जवमेव च। ज्ञानं विज्ञानमास्तिक्यं ब्रह्मकर्म स्वभावजम् ॥

śhamo damas tapaḥ śhauchaṁ kṣhāntir ārjavam eva cha jñānaṁ vijñānam āstikyaṁ brahma-karma svabhāva-jam

Serenity, self-restraint, austerity, purity, forgiveness and also uprightness, wisdom, knowledge, belief in God, are the Brâhmana duty, born of his own nature.

In plain words: Krishna lists the natural duties of a Brahmana, a priest or teacher. They are calmness, self-control, simple living, purity, forgiveness, honesty, wisdom, knowledge and faith in God.