And God saw the light, that it was good, and God divided the light from the darkness, Genesis 1:4.
Seeing that the light was beneficial, God divided the light from the darkness. The earth began to rotate on its axis as God directed the light around it. Although the sun and the moon had not yet been created, the light already present in the universe was now being channeled so that darkness—being the absence of light—abode upon the earth.
God called the light Day, and the darkness, He called Night. This marked the first day of renovation.