Fridays with the Heidelberg

Lord's Day 33

88. Q. WHAT IS INVOLVED IN GENUINE REPENTANCE OR CONVERSION?
A. Two things: the dying-away of the old self, and the coming-to-life of the new.
89. Q. WHAT IS THE DYING-AWAY OF THE OLD SELF?
A. It is to be genuinely sorry for sin, to hate it more and more, and to run away from it.
90. Q. WHAT IS THE COMING-TO-LIFE OF THE NEW SELF?
A. It is wholehearted joy in God through Christ and a delight to do every kind of good as God wants us to.
91. Q. WHAT DO WE DO THAT IS GOOD?
A. Only that which arises out fo true faith, conforms to God's law, and is done for His glory; and not that which is based on what we think is right or on established human tradition.

Throughout the Scriptures we see the following dynamic; Put Off/Put On.
Put off the old, and put on the new.
The reformers referred to this as mortification and vivification.

At conversion, we are given new life. It has already been accomplished through Christ (Justification). We are told in God's Word;

Therefore, if anyone is in Christ, he is a new creation. The old has passed away; behold, the new has come.
2 Cor. 5:17

Scripture also speaks of this same dynamic in regards to the unfinished ond ongoing process (sanctification).
Col. 3:5 -  Put to death therefore what is earthly in you

As new creations, we are given the Holy Spirit who gives us new desires. Desires for the glory of God.