The assurance that God is in full control is the proper and only effectual motivation for self-control. There is a world of difference between fleshly discipline and spiritual self-control. True self-control, in the scriptural sense, is a thing of purity, for it is a fruit of the spirit. Unless good deeds are performed under the influence of God's love or because of the assurance of His deity, they are actually works of the flesh. Inner motive must be distinguished from outward result.
External morality is often the product of sinful motives.
Stronger lusts of the flesh merely restrain weaker ones when the latter fail to serve the purpose of the former. The apostle presents these striking contrasts between the flesh and the spirit for the consideration of the Galatians. Though it is humiliating to the flesh, if we are to do what is pleasing to God, God must see to it that we do so. He not only does not need our help, but He will not have our help. He will bless us as He intends and when He intends, not otherwise or before.