What is the difference between believing God and believing in God?
Believing God is trusting Him, which becomes faith and is counted as righteousness, as Abraham believed God. Believing in God is merely recognizing that He exists somewhere, but not having anything to do with Him; that is usually the attitude of simple acknowledgement without faith.
Les explains the vast difference between believing God, which becomes faith, and simply believing in God, which is only a recognition that He is out there someplace. That second attitude says, “Who am I to have anything to do with Him?” Abraham, who had been steeped in idolatry in Ur, believed God when told to leave his family and go to a place God would show him. In Romans 4:5, Paul builds the case that Abraham was declared righteous only because he believed God.