Most of us have heard the story of creation, or read it for ourselves. We know that God rested on the seventh day. Knowing the character of God we should wonder why would He need rest? He's the Almighty. Think of it like this, when you've been working diligently on a project and it's finally finished you take a moment to stand back and take it in. Only with God, His project was perfect and He took a day to signify its completeness. So the rest He gives us is for Him who is at the center.