It tells us the result of our sinfulness. God is life and light, and He is pure and perfect. And because He is pure and perfect, His presence cannot abide sin and wickedness. And so we're separated from Him, and as a result we die, just like the limb of a tree when sawed from the main trunk. The word death is used in the Bible in the sense of separation.
Physical death occurs when the soul is separated from the body.
But there is a second death, and that, too, is separation. The great Christian intellectual C. S. Lewis once went to hear a young parson deliver a sermon. When North Carolina evangelist Vance Havner was beginning his ministry, he pastored a country church were a farmer didn't like the sermons he preached on hell. To him, death was nothing more than a painless extinction. But in 1977, Rawlings was resuscitating a man who came back from the edge of death.