Metanoia (Christianity)

In Catholic teaching, this converting from sin to God is primarily involved with the repudiation of sin first through sorrow, then confession, amendment and satisfaction. It is a change of mind based not only on changed attitude but also on external demonstration of this change through confession, fasting, etc. Lutheran teaching disagrees that mankind through its works can satisfy for sin, as this would be blasphemous rejection of Christ's work; protestant thought therefore considers repentance or change of heart to be the keystone, and that although one can lead a new life this does not or cannot make satisfaction for the past.