Fiat lux

"Let there be light" is an English translation of the Hebrew יְהִי אוֹר‎ (yehi 'or). Other translations of the same phrase include the Latin phrase fiat lux, and the Greek phrase γενηθήτω φῶς (genēthētō phōs).

The phrase comes from the third verse of the Book of Genesis. In the King James Bible, it reads, in context:

¹In the beginning God created the heaven and the earth.
²And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters.
³And God said, Let there be light: and there was light.
⁴And God saw the light, and it was good; and God divided the light from the darkness.

The Latin phrase fiat lux, from the Latin Vulgate Bible, is typically translated as "let there be light" when relating to Genesis 1:3 (Hebrew: יְהִי אוֹר‎). The full phrase is "dixitque Deus fiat lux et facta est lux" ("And said God let there be light, and there was light"), from the Greek "καὶ εἶπεν ὁ Θεός γενηθήτω φῶς καὶ ἐγένετο φῶς" (kai eipen ho Theos genēthētō phōs kai egeneto phōs), from the Hebrew וַיֹּאמֶר אֱלֹהִים, יְהִי אוֹר; וַיְהִי אוֹר‎ (vayo'mer 'Elohim, yehi 'or vayehi 'or).

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