तत्सदिति निर्देशो ब्रह्मणस्त्रिविधः स्मृतः।
ब्राह्मणास्तेन वेदाश्च यज्ञाश्च विहिताः पुरा।।17.23।।
17.23 Om-tat-sat [Om, That, Existence: Om iti brahma, Om is Brahman (Tai. 1.8.1); Tattvamasi, Thou art That (Ch. 6.8.7); and Sadeva somya idamagra asit, This was Existence alone in the beginning, O amiable one (Ch. 6.2.1)-in these texts Brahman is indicated by the words Om, tat, sat.]-this is considered to be the threefold designation of Brahman. The Brahmanas and Vedas and the sacrifices were ordanined by that in the days of yore.
17.23 Om Tat Sat: This has been declared to be the triple designation of Brahman. By that were created formerly, the Brahmanas, the Vedas and the sacrifices.
17.23. OM TAT SAT : This is held to be the three-fold indication of the Brahman. By means of that, the Vedas, and also the sacrifices had been fashioned formerly by Brahma.
Om tatsaditi nirdesho brahmanas trividhah smritah; Braahmanaastena vedaashcha yajnaashcha vihitaah puraa.
om tat sat—syllables representing aspects of transcendence; iti—thus; nirdeśhaḥ—symbolic representatives; brahmaṇaḥ—the Supreme Absolute Truth; tri-vidhaḥ—of three kinds; smṛitaḥ—have been declared; brāhmaṇāḥ—the priests; tena—from them; vedāḥ—scriptures; cha—and; yajñāḥ—sacrifice; cha—and; vihitāḥ—came about; purā—from the beginning of creation