For salvation, “repentance unto life” is just as necessary as is faith in our Lord Jesus Christ. No sinner was ever pardoned while he remained impenitent, while he remained in rebellion against God and His authority, and without submitting himself whole-heartedly to His Lordship. This involves the realization in his heart, wrought therein by the Holy Spirit, of “the sinfulness of sin” (Rom 7:13), of the awfulness of ignoring the claims of God and of defying His authority. Repentance is a “holy horror and hatred of sin, a deep sorrow for it, a contrite acknowledgment of it before God, and a complete heart forsaking of it.”
I.C. Herendeen