The flesh is a built-in law of failure, making it impossible for the natural man to please or serve God. It is a compulsive inner force inherited from man’s fall, which expresses itself in general and specific rebellion against God and His righteousness. The flesh can never be reformed or improved. The only hope for escape from the law of the flesh is its total execution and replacement by a new life in the Lord Jesus Christ.
Mark Bubeck, The Adversary, Moody Press, p. 28.