The stubborn, uncooperative nature of a mule refuses to budge no matter how much one coerces. We, on the other hand, are to be living sacrifices, offering ourselves voluntarily, doing God's will whether we want to or not. Jesus Christ set the example of subordinating His own will to God the Father's. If we are transformed by the power of God's Holy Spirit resisting letting the world squeeze us into its mold, we will undergo a complete metamorphosis of our character into the likeness of Jesus Christ. Satan will do everything in his power to prevent this metamorphosis. We need to unconditionally sacrifice ourselves to the will of God, transforming ourselves into the likeness of Christ.