One of the chief story lines of Scripture is the struggle between the arm of the flesh and the arm of the Lord. The arm of the flesh speaks of the strength of man while the arm of the Lord speaks of the strength of God. The struggle between the two is a repetitive theme throughout the entire bible – humankind’s unwillingness to hear and obey God’s voice and God’s answer with power to show humanity his utter and complete need of God. Mankind tries to prove, albeit horribly ineffectively, how much he can establish without God, while God shows humanity that without Him we can do nothing.
It’s ultimately rebellion in the heart of man that causes him to attempt to assert himself against God. Fallen humanity loves to try to prove that he doesn’t need God, that he can take care of himself and accomplish all he wants without God.