20 Heb “he called to,” meaning “he named.” God called. Seven times in this chapter naming or blessing follows some act of creation. There is clearly a point being made beyond the obvious idea of naming. In the Babylonian creation story Enuma Elish, naming is equal to creating. In the Bible the act of naming, like creating, can be an indication of sovereignty (see 2 Kgs 23:34). In this verse God is sovereign even over the darkness.
21 Heb “and the darkness he called night.” The words “he called” have not been repeated in the translation for stylistic reasons.
22 Another option is to translate, “Evening came, and then morning came.” This formula closes the six days of creation. It seems to follow the Jewish order of reckoning time: from evening to morning. Day one started with the dark, continued through the creation of light, and ended with nightfall. Another alternative would be to translate, “There was night and then there was day, one day.” The first day. The exegetical evidence suggests the word “day” in this chapter refers to a literal twenty-four hour day. It is true that the word can refer to a longer period of time (see Isa 61:2, or the idiom in 2:4, “in the day,” that is, “when”). But this chapter uses “day,” “night,” “morning,” “evening,” “years,” and “seasons.” Consistency would require sorting out how all these terms could be used to express ages. Also, when the Hebrew word יוֹם (yom) is used with a numerical adjective, it refers to a literal day. Furthermore, the commandment to keep the sabbath clearly favors this interpretation. One is to work for six days and then rest on the seventh, just as God did when he worked at creation.
23 The Hebrew word refers to an expanse of air pressure between the surface of the sea and the clouds, separating water below from water above. In v. 8 it is called “sky.” An expanse. In the poetic texts the writers envision, among other things, something rather strong and shiny, no doubt influencing the traditional translation “firmament” (cf. “dome”). Job 37:18 refers to the skies poured out like a molten mirror. Dan 12:3 and Ezek 1:22 portray it as shiny. The sky or atmosphere may have seemed like a glass dome. For a detailed study of the Hebrew conception of the heavens and sky, see L. I. J. Stadelmann, The Hebrew Conception of the World (), 37–60.
24 Heb “the waters from the waters.”

In other versions

ESVEnglish Standard Version

God called the light Day, and the darkness he called Night. And there was evening and there was morning, the first day.

And God said, “Let there be an expanse in the midst of the waters, and let it separate the waters from the waters.”

NIVNew International Version (2011)

God called the light “day,” and the darkness he called “night.” And there was evening, and there was morning—the first day.

And God said, “Let there be a vault between the waters to separate water from water.”

CSBChristian Standard Bible

God called the light “day,” and the darkness he called “night.” There was an evening, and there was a morning: one day.

Then God said, “Let there be an expanse between the waters, separating water from water.”

NLTNew Living Translation

God called the light “day” and the darkness “night.”

And evening passed and morning came, marking the first day.

Then God said, “Let there be a space between the waters, to separate the waters of the heavens from the waters of the earth.”

LEBThe Lexham English Bible

And God called the light Day, and the darkness he called Night. And there was evening and there was morning, the first day.

And God said, “Let there be a vaulted dome in the midst of the waters, and let it cause a separation between the waters.”

KJV 1900King James Version

And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day.

And God said, Let there be a firmament in the midst of the waters, and let it divide the waters from the waters.

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