Westminster Larger Catechism in modern English question number seventy-six:
Q. 76. What is repentance unto life?
A. Repentance unto life is a saving grace worked in the heart of a sinner by the Spirit and the Word of God; by which, from a sight and sense, not only of the danger, but also of the filthiness and odiousness of his sins, and upon the apprehension of God’s mercy in Christ to those that are penitent, he so grieves for and hates his sins that he turns from them all to God, purposing and constantly endeavoring to walk with Him in all the ways of new obedience.