Genesis 1:18

and to rule over the day and over the night, and to divide the light from the darkness. And God saw that it was good.

Surrounding context

1:17 God set them in the firmament of the heavens to give light on the earth,

1:18 and to rule over the day and over the night, and to divide the light from the darkness. And God saw that it was good.

1:19 So the evening and the morning were the fourth day.