Penitence. Among Protestants penitence is considered a synonym for repentance, sorrow for sin, and the turning away from it to lead a new life. It should not be confused with penance, a sacrament in the Roman Catholic Church that stresses the performance of ecclesiastically prescribed acts to make satisfaction for postbaptismal sins.
Jesus’ message, as well as that of his immediate disciples, was characterized by the call for men to repent (Mark 1:15; 6:12; Luke 10:13). The Greek term metanoeo holds two ideas: “to change one’s mind” and “to regret or feel remorse.” Thus, repentance is one aspect of conversion, the other being faith. Together they form one experience in which a person turns from sin to Christ.
--B. L. Shelley,
Evangelical Dictionary of Theology,
Second Edition, p. 898