“Om Tat Sat — this is declared the threefold designation of Brahman (trividhā brahmaṇaḥ niḥśabdaḥ)…” K unfolds the sacred formula as a consecrating device (17.23–27). Om — the primal syllable — is uttered at the outset of every act of sacrifice, gift and austerity by the knowers of Brahman, aligning the act with the Absolute at its source. Tat (“That”) — pointing beyond the finite — names the spirit in which acts of sacrifice, austerity and gift are performed without desire for fruit, by those who seek liberation. Sat (“the Real / the Good”) — is used for existence, for goodness, and for every praiseworthy action; it also marks steadfastness in sacrifice, austerity and gift, and any action done for His sake. And the counterpoint, the great warning of the chapter (17.28): “Whatever is offered, given or done, and whatever austerity is performed, without faith, is called Asat (asad ity ucyate) — it is nothing, here or hereafter.” So the whole chapter returns to its beginning: not the outer correctness of the rite but the faith and guṇa animating it decide its worth. An act soaked in sattvic faith and consecrated by Om Tat Sat is real and fruitful; the most elaborate rite performed faithlessly is asat — a hollow shell. This directly answers Arjuna’s opening question (17.1): the faithful but irregular worshipper is judged not by his lapse from rule but by the guṇa of his faith — and sattvic faith, even when technically irregular, is not lost.