Genesis 2:21

And the Lord God caused a deep sleep to fall upon Adam, and he slept; and He took one of his ribs and closed up the flesh instead thereof. Sleep is the natural restorer of man's bodily and mental vigor and not the result of sin. But here was the unusual factor: God purposely caused a deep sleep to fall upon Adam, thus taking from him all consciousness of the outside world and of his own life. He then removed one of the man's ribs, closing up the vacant space with flesh.