Brihadaranyaka Upanishad 5.4: M 5 / K 4

5.4.1

tadvai tadetadeva tadāsa satyameva sa yo haitaṃ mahadyakṣaṃ prathamajaṃ veda satyaṃ brahmeti jayatīmām̐llokānjita innvasāvasadya evametaṃ mahadyakṣaṃ prathamajaṃveda satyaṃ brahmeti satyam̐ hyeva brahma

Thatfootnote{The pronoun ‘Tat’ (that or it) occurs thrice in the text. The last two (as well as the particle ‘vai’) have been omitted in the translation to avoid confusion. They are explained in the commentary.} (intellect-Brahman) was but this—Satya (gross and subtle) alone. He who knows this great, adorable, first-born (being) as the Satya-Brahman, conquers these worlds, and his (enemy) is thus conquered and becomes non-existent—he who knows this great, adorable, first-born (being) thus, as the Satya-Brahman, for Satya is indeed Brahman.

5.4.1.p1

iti pañcamādhyāye caturthaṃ brāhmaṇam