This grows out of an ongoing conversation with Pr. Weedon and others, and yet another installment of that conversation today at lunch:
Do we actually grow in God's grace? Once brought to life and faith in our loving, merciful God, does God's grace actually change us, or transform us? Sometimes we may focus so much on the "forensic" character of God's justification of us sinners - a point that is quite true and essential indeed - that we lose sight of how His grace, mercy, and love also change or transform us. We should remember that it's not a matter of either/or, but rather a truth of both/and. Yes, God's grace does work to change and transform us!
St. Peter can give us such sweet Gospel (as in 1 Peter chapters 1 & 2) and yet still exhort us to "Grow in the grace and knowledge of our Lord and Savior Jesus Christ" (2 Peter 3:18). St. Paul can teach us quite well on God's justification of the sinner (see Romans 3-5) and yet still exhort us, "by the mercies of God, to present [our] bodies as a living sacrifice, holy and acceptable to God, which is [our] spiritual worship" (Romans 12:1). Martin Luther can even teach us that Baptism means daily dying to sin and its desires and rising to newness of life in Christ (Small Catechism on Baptism). This must be why Luther can be quite comfortable explaining more in his Large Catechism, again when he discusses Baptism:
For this reason let everyone value his Baptism as a daily dress...in which he is to walk constantly. Then he may ever be found in the faith and its fruit, so that he may suppress the old man and grow up in the new. For if we would be Christians, we must do the work by which we are Christians" (Concordia, p. 431).Not only are we forensically forgiven by the sacrifice of Jesus Christ on the cross, but we also get to grow in His grace as His holy people, growing more and more into the image of Christ Himself!