Worship of the gods, the twice-born, teachers, and the wise; purity, uprightness, celibacy, and non-violence — this is called the austerity of the body.

Krishna now turns to the threefold classification of tapas (austerity, discipline) — first describing what constitutes austerity of the body. It is not primarily physical punishment but the disciplined, respectful orientation of the body's actions: the worship of those worthy of worship (gods, the learned, teachers, the wise), the maintenance of outer and inner purity (śauca), the practice of uprightness (ārjava — transparency in word and deed), brahmacharya (disciplined use of vital energy, traditionally translated as celibacy but more broadly meaning the direction of life-energy toward the highest), and ahiṃsā (non-violence). These are the austerities of the body — not what is done TO the body, but what the body is trained to DO.