One of the figures that is essential to examine in the ongoing debates over sanctification and good works is Francis Pieper. If one studies Pieper's Dogmatics, it becomes immediately apparent that he is not afraid of emphasizing the importance of justification and good works. He writes:
"The fact that sanctification in this life will always be imperfect must not be put forward as an excuse for the neglect of sanctification. On the contrary, it is God's will and the will of the Christian that he strive after perfection; he wants to be fruitful, not only in some, but in all good works. It is the characteristic of the Christian life and the will of the new man that he refrain from every sin. The Christian is eager to serve God in all good works...The Christian who does not strive to serve God alone is perilously close to losing his Christianity...Unsparing self-denial marks the Christian life." CD III, 33
After this, Pieper talks about how the drive to perfection (which is of course not achievable) should not cause us to despair, but should point us again to the grace of God found in the Gospel. It's something of a circle. We see our sin, look to the Gospel, then in light of that message strive to live holy lives. When we fail at leading such holy lives, we are once again pointed to the Gospel. But note that Pieper continually emphasizes our "striving," and not neglecting sanctification. In other words, the Christian should not simply be content to be "weak on sanctification," but should pray and strive for holiness. This is not to be done, of course, for the sake of gaining or retaining salvation, but because the Christian desires to live a God-pleasing life.
Pieper questions which evil is greater, "perfectionism or indifference to sanctification?" and he argues that both are equally bad. Pieper writes that "The Bible says to the 'Christian worldling': 'This ye know that no whoremonger, nor unclean person, nor covetous man, who is an idolater, hath any inheritance in the kingdom of Christ and of God. Let no man deceive you with vain words; for because of these things cometh the wrath of God upon the children of disobedience. Be not ye therefore partakers with them." (CD III, 34) It is clear that Pieper is concerned with both legalism and indifference to sanctification. Some in the debate today seem to think that legalism is the only real problem the church has to face, and that indifference to sanctification is almost a virtue, because it shows one's trust in justification.
Good works need to be preached, and one should strive for them. These works are to be in accord with God's law. Pieper writes that, "everything which the Christian performs in obedience to God's will is good and great, whether me prize it or not." (CD III, 39) He argues that "Christians should not be satisfied with having performed this or that good work, but they should become rich in good works...They should not sit and home and wait to be importuned to do good works, but they should go out and seek opportunities to do good works; they should be 'zealous of good works.'" (CD III, 47) Clearly, for Pieper, good works are not purely spontaneous, but one has to actually try and do them.
Preachers have a duty to proclaim the importance of good works. "Secondly, in urging members of their churches to become 'rich in good works,' pastors should not be deterred from doing this boldly and resolutely, without any fear or faltering, by the thought that this insistence on good works might crowd out its central position on the doctrine of justification without works. Only if one does not know the Scriptural doctrine of justification by faith will he be timid in asking for a multitude of good works." (CD III, 48) Pieper then makes the necessary point that encouragement unto good works should always be done in light of the gospel. In one place, Pieper urges: "In addition, God has instructed the teachers and watchmen in His Church to give attention not only to the quality but also the quantity of works performed by Christians." (CD III, 48) He cites Titus 3:8 for justification in doing so. What all of this makes apparent is that Pieper saw encouragement unto good works as a necessary part of the pastoral office. He did not view this as somehow minimizing the truth of simul iustus et peccator or the centrality of justification.
Pieper did not shy away from discussing the doctrine of sanctification and the importance of good works. These are central to the Christian life, the teaching of Scripture, and the pastoral office.