John Calvin Commentary Genesis 1:4

"And God saw the light, that it was good: and God divided the light from the darkness." — Genesis 1:4 (ASV)

And God saw the light. Here, Moses portrays God surveying His work, so that He might take pleasure in it. But He does this for our sake, to teach us that God has made nothing without a specific reason and design. And we should not understand the words of Moses as if God did not know that His work was good until it was finished. Instead, the meaning of the passage is that the work, as we now see it, was approved by God.

Therefore, nothing remains for us but to acquiesce in this judgment of God. And this admonition is very useful. For while humans ought to apply all their senses to the admiring contemplation of God's works, we see what license they really allow themselves in detracting from them.