“be filled with the Spirit” (Ephesians 5:18) is to be controlled by the Holy Spirit. This is a present continuous action and requires a believer to be (a) daily yielded to God, (b) daily in repentance with confession with godly sorrow, (c) daily allowing the word of God to richly indwell the inner man. Being controlled by the Holy Spirit empowers a believer (a) daily in spiritual battle (Spirit versus flesh) and, (b) daily in living out the person and character and conduct of Christ and in being obedient to the will of God.
The Natural Man
All mankind has a center to their being. At that center is a throne. The Natural Man himself is sitting on that throne. No matter what stage of life you are in; if Jesus is not sitting on that throne, you have not come to salvation.