Shloka 18
शकुनि (हिरण्मय-पक्षी) उपदेशः — Vighasāśin and the Difficulty of Gārhasthya
एतद्वो<स्तु तपोयुक्त ददामीत्यूषिचोदितम् । तस्मात् तत् तद् व्यवस्थानं तपस्वितप उच्यते
etad vo 'stu tapoyuktaṁ dadāmīty ūṣicoditam | tasmāt tat tad vyavasthānaṁ tapasvitapa ucyate |
“此当归于汝等，具足苦行（tapas），我予以赐与”——这是受灵感启示的圣见者所宣告的。因此，对每一项所规定的吠陀义务坚定不移地奉行，便称为修行者之“苦行”：以内在的克己为本，纪律严明地从事祭祀之业，由此得蒙赐予所愿之果。
अजुन उवाच
Educational Q&A
Tapas is not only physical austerity; for a practitioner it can mean unwavering, disciplined adherence to one’s prescribed Vedic duties—especially sacrificial action—performed with inner restraint and seriousness, which becomes the basis for receiving the intended fruits.
A seer’s pronouncement is cited: the rite should be performed ‘with tapas,’ and the fruits will be granted. From this, the text concludes that fully committing oneself to the proper performance of those specific rites is itself the ascetic’s tapas.