Charles Spurgeon Commentary Genesis 1:5

"And God called the light Day, and the darkness he called Night. And there was evening and there was morning, one day." — Genesis 1:5 (ASV)

It is a good thing to have the right names for things. An error is often half killed when you know the real name of it; its power lies in its being indescribable; but as soon as you can call it "darkness," you know how to act towards it. It is a good thing also to know the names of truths, and the names of other things that are right. God is very particular in the Scripture about giving people their right names. The Holy Spirit says, "Judas, not Iscariot," so that there should be no mistake about the person intended.

Let us also always call persons and things by their right names: "God called the light Day, and the darkness he called Night." "And the evening and the morning were the first day." Darkness first and light afterwards. It is so with us spiritually; first darkness, then light. I suppose that, until we get to heaven, there will be both darkness and light in us; and as to God's providential dealings, we must expect darkness as well as light. They will make up our first day and our last day, till we get where there are no days but the Ancient of Days.