Bereshit 1:4

וירא אלהים את האור כי טוב ויבדל AND GOD SAW THE LIGHT THAT IT WAS GOOD, AND GOD CAUSED A DIVISION — Here, also, we must depend upon the statement of the Agada: He saw that the wicked were unworthy of using it (the light); He, therefore, set it apart (ויבדל), reserving it for the righteous in the world to come (Chagigah 12a). But according to the plain sense explain it thus: He saw that it was good, and that it was not seemly that light and darkness should function together in a confused manner. He therefore limited this one’s sphere of activity to the daytime, and this one’s sphere of activity to the nighttime (see Genesis Rabbah 3:6).

וַיַּ֧רְא אֱלֹהִ֛ים אֶת־הָא֖וֹר כִּי־ט֑וֹב וַיַּבְדֵּ֣ל אֱלֹהִ֔ים בֵּ֥ין הָא֖וֹר וּבֵ֥ין הַחֹֽשֶׁךְ׃

And God saw the light, that it was good: and God divided the light from the darkness.