17:23
ॐतत्सदिति निर्देशो ब्रह्मणस्त्रिविधः स्मृतः ।
ब्राह्मणास्तेन वेदाश्च यज्ञाश्च विहिताः पुरा ॥१७- २३॥
ॐतत्सदिति निर्देशो ब्रह्मणस्त्रिविधः स्मृतः ।
ब्राह्मणास्तेन वेदाश्च यज्ञाश्च विहिताः पुरा ॥१७- २३॥
AUMtatsaditi nirdesho brahmaNastriwidhaH smRRitaH ।
braahmaNaastena wedaashcha yadnyaashcha wihitaaH puraa ॥१७- २३॥
Source: Automatic ITRANS Transliteration
"Aum tat sat," so is remembered the threefold reference to Brahman.
Brahmins and Vedas and sacrifices were historically ordained.
Source: Milind S. Pandit
"OM TAT SAT" is said to be the threefold name of Brahman. The Braahmana, the Vedas, and the Yajna were created from this in the ancient time.
From the beginning of creation, the three syllables--om tat sat--have been used to indicate the Supreme Absolute Truth [Brahman]. They were uttered by brahmanas while chanting Vedic hymns and during sacrifices, for the satisfaction of the Supreme.
Source: Bhagavad Gita As It Is