Peace, humility and now power. And the reason it's powerful is because it's God's. Grace is not mere permission to serve. It is not mere obligation to serve. It is not mere calling to serve.
Grace is power to serve.
Grace is God's presence in you freeing you from the power of sin to serve the body of Christ. The second way Paul illustrates the humility of this sound judgment is by saying that faith is a gift. If you come to terms with the fact that God measures out faith in various measures you will think with sound judgment and you will not think more highly than you ought to think. That is thinking more highly than one must think. Because, even though faith is indeed an act of the human heart, it is first a gift from God.