This series is taken from Chafer's Systematic Theology by Lewis Sperry Chafer, Volume III, Chapter XX (under Soteriology):
But a moment need be devoted to this error which prevails among certain groups of zealous people. The Scripture employed by advocates of this error is that which applies only to Christians. The passage reads: "If we confess our sins, he is faithful and just to forgive us our sins, and to cleanse us from all unrighteousness" (1 John 1:9). This declaration, as has been seen, is addressed to believers who have sinned and presents the ground on which such may be restored to fellowship with God. The notion that restitution must be made before one can be saved is based on the God-dishonoring theory that salvation is only for good people,
and that the sinner must divest himself of that which is evil before he can be saved. In other words, God is not propitious respecting sin; He is propitious toward those only who have prepared themselves for His presence and fellowship. Over against this, the truth is ignored that the unregenerate person cannot improve his fallen condition and, if he could, he would be bringing merit to God where merit is wholly excluded to the end that grace may abound and be magnified through all eternity. The preacher must ever be on his guard to discourage the tendency of the natural man to move along lines of reformation rather than regeneration. Those who are serious regarding their lost estate are best helped by that body of truth which declares that God, through Christ, must save and will save from all sin; that He must and will deal with the very nature which sins; and that He must and will rescue men from their estate under sin. There are various ways by which the natural man proposes to be saved and yet retain his dignity and supposed worthiness, and one of these is the contention that sin must be confessed and restitution made as a human requirement in salvation. It is God who justifies the ungodly (Rom. 4:5); it is while men are "enemies, sinners, and without strength" that Christ died for them (Rom. 5:6–10); and all their unworthiness is accounted for by Christ in His death. There is a duty belonging only to Christians—to set things right after they are saved—and there should be no neglect of that responsibility. It therefore remains true that those who are saved are saved on the one condition of believing upon Christ.