The word is הוּא (hu), the Hebrew pronoun “he.” Tiny, unremarkable on its own — and yet, paired with אֲנִי (ani), “I,” it forms one of the most loaded phrases in the Hebrew Bible. אֲנִי הוּא (ani hu), literally “I — he,” is what English Bibles render “I am he.” Hebrew doesn’t need a linking verb here; the two pronouns simply stand side by side, “I” and “he,” and the sense is “I am the one.” But in the right mouth, in the right book, that bare juxtaposition becomes God’s signature.

That book is Isaiah — specifically chapters 40 through 55, where the LORD declares, against the idols of Babylon, that he alone is God. “I, the LORD, the first, and with the last; I am he” (Isaiah 41). “That you may know and believe me and understand that I am he. Before me no god was formed, nor shall there be any after me” (Isaiah 43). It returns in 46, in 48 — God’s recognition-line, the way the one true God identifies himself over against the gods who are nothing. I am he. I am the one. There is no other. The hu — “he” — is the predicate of that self-naming: God isn’t pointing to anything outside himself for identity. He is simply he, the one, complete.

Here is why hu matters so much for the New Testament, and it’s the hinge both books turn on. The popular reading of John 8:58 says Jesus is quoting the burning bush, Exodus 3:14. But that reading has a real problem: in the Greek that John’s audience actually used, the burning-bush name wasn’t rendered as a bare egō eimi. It came out ἐγώ εἰμι ὁ ὤν (egō eimi ho ōn), “I am the One Who Is,” and the name God hands Moses is just the back half, ho ōn. Jesus in 8:58 doesn’t say that. He says only egō eimi. So the Exodus link doesn’t quite fit the words.

But Isaiah’s ani hu does — exactly. When those Isaiah passages were translated into the Septuagint, the signature phrase “I am he” was rendered, again and again, with precisely the two words Jesus speaks: the absolute ἐγὼ εἰμί (egō eimi), no predicate, “I am [he].” That match is what makes ani hu the strongest Old Testament anchor for the divine-name reading of John 8:58. A Greek-speaking Jew soaked in Isaiah, hearing a man stand in the temple and say egō eimi with that time-defying grammar wrapped around it, could well have heard not the burning bush but Isaiah’s God declaring, “I am he” — the recognition-line of the one and only God.

What the first audience heard in hu was God’s own “he” — the second half of the line by which the LORD named himself the only God. And when its Greek echo landed in the temple, the people closest to Isaiah heard the same claim taken onto a human voice.