The existence of this fight within needs to be pointed out to the new Christian, who is struggling to understand what God has done in him, and may doubt the reality of his conversion when he sees that sin is still active within him. Surely, he thinks, if I were a true Christian I would not still desire to do evil. No, says Paul, even the true believer still experiences this strange struggle within. This has to be experienced to be believed for we would otherwise find it hard to imagine how two conflicting wills could coexist in the same person. This battle causes us distress, for we feel ourselves to be divided. If we side with the flesh, we know the spiritual nature will die and that causes us pain since all that we hold dear is associated with God’s work within us. But if we side with the new nature, the old nature also complains bitterly that part of us is about to be destroyed. This conflict exhausts us as we are pulled first one way and then the other. The outcome however is not in doubt, for the believer has already made the vital choice at conversion: he has so identified with the Lord that he has been willing for the old nature to be destroyed and the new nature alone to live. For this reason Paul describes the believer as having died to sin with Christ. There can be no true conversion without death, for nothing less than this in true repentance. Repentance involves not just a temporary, vacillating departure from the old life of sin, but a permanent eternal departure never to return again, which involves death to what we were before. It is called death because it is a change which puts the old life beyond reach, so that we cannot return to it again. Yes, the believer may backslide, but if there has been a true work of conversion, the death to sin that we experienced and the resurrection to a new life will reassert itself.
He identifies one of these natures with the real self: ‘You do not do the things that you would’. Which nature is he referring to? As in Romans 7:24 it is the new nature that represents the real person, and the old nature has become something which the believer is struggling to put to death. He cannot do the things that he wishes to do fully and nor can the flesh do the evil things that it wishes fully, for in both cases the other nature is active to resist the intention.
How is this struggle different to the struggle which goes on in the heart of an unbeliever when his conscience raises its voice to resist some course of action? In such a case the man cannot say that he loves God’s law after the inward man. There is nothing in him that rejoices at the voice of conscience or wants it to speak. He is motivated entirely by fear of punishment and not by genuine desire for what is good or for what is loved by the Spirit. He may comply with conscience, but it is only to avoid inward pain, and in his attempts to avoid one sin he often substitutes another in its place.