Sanskrit
देवद्विजगुरुप्राज्ञपूजनं शौचमार्जवम् । ब्रह्मचर्यमहिंसा च शारीरं तप उच्यते ॥
devadvijaguruprājñapūjanaṃ śaucam ārjavam brahmacaryam ahiṃsā ca śārīraṃ tapa ucyate
Translation
Worship given to the Gods, to the twice-born, to the teachers and to the wise, purity, straightforwardness, continence and harmlessness, are called the austerity of the body.
Annie Besant · The Bhagavad-Gita, translated by Annie Besant (4th ed., 1922) — Wikisource · Public Domain
Explanation
Having graded food and sacrifice by guna, the chapter now redefines tapas itself before grading it — verses 14 through 16 first split austerity into three domains (body, speech, mind) rather than three qualities, and only in verse 17 does the guna-grading resume. Bodily austerity here is notably social rather than solitary: reverence toward gods, elders, and the learned, plus purity, honesty, celibacy, and non-harm (ahiṃsā) — a far cry from the self-mortification condemned back in verses 5-6.