Repentance is a change that occurs in the heart (the Bible “mind”). This change of mind describes the change in one’s disposition and priorities, the exchange of an earthly mind set to a heavenly mind-set.
The call to be a disciple of Jesus requires this repentance. Paul emphasizes its necessity in Acts 17:30-31. Both Jesus and John the Baptizer preached, “Repent, for the kingdom of heaven is at hand” (Matthew 3:2, 4:17). Obviously, a person must be informed of that to which he or she must convert. The sermon on the Mount gives us a model that reflects this radical change of thinking. The beautitudes, in particular, describe a new way of thinking for the would-be disciple.
Associated with a change of heart is a change in actions. One’s actions reveal what is in the heart (Mat. 12:33, 15:18-19). A clean mind or a pure heart will produce good things while a corrupt mind will produce evil things. Jesus taught that a corrupt tree cannot produce good fruit and that people, like trees, can be known by their fruits (Mat. 7:17-20). When the Pharisees came out to John’s baptism, he said, “Bring forth fruit worthy of repentance.”