Commentary: At first, this made no sense to me; how would you be contrite out of love? As it turns out, that's the point. The idea is that we should be sorry for sins because we have love for God in our hearts (point: we have good hearts) rather than a selfish fear of punishment. The clearest Biblical examples refuting this are the jailer at Philippi and the crowd at Pentecost. Before conversion, there is no love for God in our hearts; they are hostile rather than good.
As I began writing this post, I started to wonder if this applies to us only before conversion; after conversion, can we be sorry for our sins because they hurt God? Well, let's begin with four pertinent details of Lecture 22 to provide a background for investigation.
After conversion, the Law doesn't stop working. It still acts as a mirror; Romans 3: 20 states, "Through the law we become conscious of sin." Walther comments, "Here the apostle states the function of the Law: it produces, not love, but the knowledge of sin." He also later writes, "Even when there is love of God in a person's heart, it will be spoiled by the devil." Walther quotes the Apology of the Augsburg Confession, "When we speak de contritione, that is, regarding genuine contrition, we cut out those innumerable questions which they cast up, viz., whether a person's contrition flows from love of God or from fear of punishment. For these are nothing but mere words and a useless babbling of persons who have never experienced the state of mind of a terrified conscience. But we say that contrition is the true terror of conscience, when it begins to feel its sin and the anger of God against sin and is sorry for having sinned."
With that said, I'm not going to answer the questions yet. Lecture 23, which I've read, expands upon the subject, and I also want to check out a paper from the WLS Essay file, Rev. Allen Lindke's "Apology, Article XII (V): Of Repentance."
Vocab:
Τοῦτό ἐστι τὸ σῶμα μου = Touto mou estin to soma = (literal translation) "This is the body of me," Jesus' words in the Lord's Supper
Nitimur in vetitum semper cupimusque negata = We are ever striving after what is forbidden, and coveting what is denied us.