According to John Frame, "We can think of [experiential] sanctification as the outworking of the new life given in regeneration." It involves the gradual, incremental and (S)piritual work of both putting to death the remains of "indwelling sin" as well as putting on the likeness of Christ. While we work out the salvation given to us, it is God who works in us, both to will and to work for His sovereign good pleasure. (Phil 2:13).
“Progressive sanctification has two parts: mortification and vivification, “both of which happen to us by participation in Christ,” as Calvin notes (Calvin, Institutes 3.3.2, 9 The “mortification / vivification” distinction was first formulated by Melanchthon in his Commentary on Romans (Corpus Reformatorum). These occur simultaneously and continuously throughout the Christian life, rather than in stages. Christ’s death alone is atoning, and cannot be repeated. He died for our sins, but we die to our sins. Christ took up his cross once and for all as a sacrifice for sin, but he calls his disciples to “take up [their] cross daily,” facing persecution from within and without (Lk. 9:23). Although we have died definitively to the law and to sin (Paul uses the analogy of remarriage after a death in Romans 7: 1-6; cf. Gal. 2:19), we continue to struggle inwardly with our new identity (Ro. 7:7-24). Subjectively experiencing this definitive reality signified and sealed to us in our baptism requires a daily dying and rising.” (Michael Horton, The Christian Faith, etc., page 661)