What is repentance unto life?
Repentance unto life is a saving grace, (2 Tim. 2:25) wrought in the heart of a sinner by the Spirit (Zech. 12:10) and word of God, (Acts 11:18,20–21) whereby, out of the sight and sense, not only of the danger, (Ezek. 18:28,30,32, Luke 15:17–18, Hos. 2:6–7) but also of the filthiness and odiousness of his sins, (Ezek. 36:31, Isa. 30:22) and upon the apprehension of God’s mercy in Christ to such as are penitent, (Joel 2:12–13) he so grieves for (Jer. 31:18–19) and hates his sins, (2 Cor. 7:11) as that he turns from them all to God, (Acts 26:18, Ezek. 14:6, 1 Kings 8:47–48) purposing and endeavouring constantly to walk with him in all the ways of new obedience. (Ps. 119:6,59,128, Luke 1:6, 2 Kings 23:25)
The Westminster Larger Catechism: With Scripture Proofs. (Oak Harbor, WA: Logos Research Systems, Inc., 1996).