'Change Of Heart' in the Bible

And [the need for] a change of heart and life in order to receive the forgiveness of sins [from God] will be preached in Jesus' name [i.e., by His authority] to people of all nations, beginning from Jerusalem.

For the sorrow that God desires produces repentance [i.e., a change of heart and life] that leads to salvation, and which brings no regrets. But the sorrow of the world [i.e., sorrow for wrongdoing for reasons unrelated to God or moral principles] produces [spiritual] death.