Gerhard and Walther

To sum up, He [Jesus] began everything with prayer and concluded everything with thanksgiving in order to teach us that we much more are obligated to thank God the Lord for all His benefits and blessings.—Johann Gerhard, Schola Pietatis III:370.

Sanctification, on the contrary, does not happen suddenly. It occurs gradually, and it continues until the end of our life. Justification is immediately perfect. Each one who is justified instantly receives the full forgiveness of his sins, the complete righteousness of Christ, and a new status as a child of God. Sanctification, which follows justification, begins weakly and grows until death, but it never comes to perfection.—C. F. W. Walther, God Grant It!, p. 671.