Are Christians totally under God's control and power?
Yes, Christians are totally under the control and power of the sovereign God, and nobody can supersede His power. Nothing can separate believers from the love of Christ or the love of God. They cannot remove themselves from Christ's body by their own sin any more than someone else can.
Les explains that the Scripture says God will never cast us out, and a person cannot cast himself out by committing some horrible sin. He says you cannot touch yourself so far as being in that position in the body of Christ any more than someone else can. Believers are totally under the control and power of the sovereign God, and nobody can supersede His power. Les says this is what Paul is literally screaming in the closing verses of Romans 8, which are like the crescendo of a great orchestra: the sound builds and builds, then the cymbals clash and get your attention. The point is that nothing can separate us from the love of Christ, the love of God.