It has come to my attention that there have been some more people who have responded to what I have said about sanctification. I don't want to attack any brother pastors who are faithful workers for the kingdom of God. So, I will not do that. But what I do want to do is clarify some things, because a lot of this comes down to misunderstanding.
First, I want to say that I don't think anyone should be checking their progress on sanctification. We grow in grace as the Bible tells us we do; that does not mean that we need to be looking at ourselves, hoping for progress. You won't find it. And there is a good reason you won't find it; the more you grow in grace, the more sensitive you are to your sin. Thus, others might see change in you, but you won't.
Second, progressing in the Christian life isn't about "becoming less sinful." Rather, it's about the raising up of the new man and the killing of the old. This is a work that is done as the Law kills, and the Spirit brings life. Thus, the affections and actions of the new man are more and more prominent throughout the Christian's life. We still have a sin nature, which effects all that we do. However, the new nature gains victory over the old, and rules more and more. This causes us to obey the desires of the new man over the old. This isn't opposed to viewing conversion as a daily reality, because it is. However, that daily repentance has actual affects in our lives.
Third, I'm not stuck on the term "progressive sanctification." The Lutheran Dogmaticians distinguish between the "narrow sense" of sanctification, and the "broad sense" of sanctification. The narrow sense is described as growth. Thus, progressive sanctification seemed to be an appropriate term because it basically stayed within the Dogmatic Lutheran tradition. If you are afraid of confusing this with the Reformed or Wesleyan doctrines of sanctification, then I understand if you don't use the term. I have no issue with that. I personally prefer speaking of Christification, because that gets at both the Patristic sense of "theosis" in the Christian life, as well as the Christological nature of growth. Sanctification isn't about moral progress; it's about a deepening communion with God which demonstrates itself through increasing works of love.
Fourth, I don't condone judging the sanctification of other people. I heard someone say that I equated cursing with not being sanctified; not saved. I don't do this at all. I choose not to use profanity. I don't think it is a wise think for a Christian to do, because it can give a bad witness to the world. That being said, I don't ever get on the case of my friends who do. The only time that I would is if foul language is being used in the pulpit. What I was criticizing in my post was not specifically cursing, smoking, or drinking, but doing those things in excess, and doing them in an arrogant spirit of "I can use my Christian liberty to do whatever I want and do it in your face." In other words, I am going to do these things just to offend people.
Fifth, I don't think that we are sanctified by our own efforts. We are sanctified by God as he comes to us through word and sacrament. He raises up the new man within us, and kills the old. But, at the same time, the new man actually does good works. As Augustine says, "God saves us, though not without us." We cooperate with God's grace, because he has renewed our wills and given us an affection for himself, and his commands.
Finally, I don't think that the Law sanctifies. Sanctification comes as a result of the gospel. The Law kills, but the Spirit gives life. But that doesn't negate the fact that we should tell Christians to do good works. Paul, the Confessions, Pieper, Walther, etc. both talk about encouraging people to do good works, and the Gospel as the sole means of sanctification. These are not mutually exclusive ideas.
And one additional question that I need to answer is, "Why is this teaching important?"
The first response I would have to this is simply that the Bible teaches it, so we should believe it and believe that it is important. Second, there are some abuse the gospel and say "The Christian isn't progressively sanctified by the Spirit, thus I might as well just live in sin because I'm saved anyway." There are people who live this way; I have met some of them. This guards against that error. Third, this should affect our prayer life. We should pray that the Lord would increase our love, and our hatred for sin. We should also pray for our brothers and sisters in Christ, that they too might grow in grace. Fourth, it also is an encouragement when we look to our brothers and sisters and see how they have grown. It is a chance for us to rejoice in God's goodness, that he really does work within his people!