Repentance is always set forth as the path to remission of sins and restoration to God’s favor, impenitence as the road to ruin (e.g., Luke 13:1–8)

Repentance is a fruit of faith, which is itself a fruit of regeneration. But in actual life, repentance is inseparable from faith, being the negative aspect (faith is the positive aspect) of turning to Christ as Lord and Savior

The idea that there can be saving faith without repentance, and that one can be justified by embracing Christ as Savior while refusing him as Lord, is a destructive delusion.

True faith acknowledges Christ as what he truly is, our God-appointed king as well as our God-given priest, and true trust in him as Savior will express itself in submission to him as Lord also. To refuse this is to seek justification through an impenitent faith, which is no faith.

In repentance, says the Westminster Confession,

a sinner, out of the sight and sense not only of the danger, but also the filthiness and odiousness of his sins, as contrary to the holy nature, and righteous law of God; and upon the apprehension of his mercy in Christ to such as are penitent; so grieves for, and hates his sins, as to turn from them all unto God, purposing and endeavoring to walk with him in all ways of his commandments. (XV.2)

This statement highlights the fact that incomplete repentance, sometimes called “attrition” (remorse, self-reproach, and sorrow for sin generated by fear of punishment, without any wish or resolve to forsake sinning) is insufficient. True repentance is “contrition,” as modeled by David in Psalm 51, having at its heart a serious purpose of sinning no more but of living henceforth a life that will show one’s repentance to be full and real (Luke 3:8; Acts 26:20). Repenting of any vice means going in the opposite direction, to practice the virtues most directly opposed to it.