Do you really believe that sanctification is furthered by rules and if so in what way? I fail to see any way that rules effectively “further” sanctification.
A rule like “children obey your parents” does in fact further sanctification. It is essential to the sanctification of children. Regeneration itself does not bring any revelation as to the particular nature of the sanctified life. Regeneration does not impart any knowledge of the standard of conformity required for holiness. Regeneration is the impartation of a new disposition (or nature; see here). The regenerated person now has a disposition toward God, toward obedience to God. He has a desire to obey God, though the old disposition (or nature) is not immediately removed. Rules like “children obey your parents” further sanctification in that they give the standard of holiness and thus direct the regenerated person toward holiness. True, the rule in and of itself cannot bring about holiness apart from the regenerated heart and empowering Spirit, but the regenerated heart cannot be sanctified without the rule. Regeneration does not impart with it a knowledge of the the obedience required for sanctification.
It might be assumed, however, that people who are regenerated sort of automatically know the standards of holiness and thus don’t need any “rules.” Children, even in non-Christian homes, usually grow up being taught to obey their parents, and thus when they are regenerated, their new disposition leads them toward obedience to their parents, so that it might seem they need no rule to further their sanctification in this area. But that is because they are already aware of the God-given rule of obedience to parents. Admittedly, since we are all created in the image of God, everyone has a general sense of right and wrong written on our hearts (Rom 2:14-15). But of course this is imperfect at best and not sufficient for the holiness God requires.
We might consider the case of sexual immorality, particularly premarital sex. In today’s American culture many young people and those who teach them believe that premarital sex is perfectly normal and that it would be foolish to enter into marriage with someone with whom one has not had sex. Such a person who comes to Christ does not necessarily know, simply because of their regeneration, that having sex with their girlfriend or boyfriend is now sinful. They need a command, an exhortation, a rule that such conduct is contrary to God’s standard of holiness. They need to know this rule if their sanctification is to be furthered. Paul’s culture was similar to what we now face in ours in the realm promiscuity, so that we commonly see in his writings warnings about sexual immorality. People in his time did not automatically know that sexual immorality was forbidden when they came to Christ. They needed a rule (1 Cor 6:18) to further their sanctification.
I think what is behind this uncomfortableness with the role of rules in sanctification is a misunderstanding of the contrast between law and grace that is set forth in Scripture, particularly in a text like Rom 6:14, “For sin shall no longer be your master, because you are not under the law, but under grace.” This is taken to mean that there is some sort of absolute antithesis between law and grace such that any law or “rule” is antithetical to the Christian experience (for more, see here). This aversion to law in sanctification is found among some dispensationalists. Alva J. McClain in his generally helpful book Law and Grace goes to great lengths to disallow any connection between the idea of law and the believer (54). Similarly, Charles Ryrie in his book The Grace of God denies the role of law in sanctification because of the absolute antithesis he draws between law and grace (104). Ryrie thus says the Mosaic Law could not and did not sanctify individuals who were regenerate. But just the opposite is true. David speaks of the man who “delights in the law of the Lord” and goes on in Psalm 1 to describe its sanctifying effects. Sanctification for the regenerate comes through obedience to the will of God set forth in rules, including its Mosaic form. But the Law, as part and parcel of the Mosaic covenant, provided within itself no power to obey that Law. Regeneration was not a guaranteed part of the old covenant, as it is in the new covenant (Jer 31). The problem was not with the Law itself but the inability of unregenerate Israelites to obey it. But obedience to the Mosaic Law brought sanctification to regenerate Israelites like David.
This rejection of the Mosaic Law as a sanctifying agent in the Old Testament leads Ryrie and others to conclude that that the problem with the Mosaic Law was that it was law. Thus when we come to the New Testament, law or “rules” are commonly seen as antithetical to sanctification. This idea shows up in the writings of various authors, recently those of Tullian Tchividjian. This anti-rule sentiment often leads to a very passive view of sanctification and the idea that instead of rules the believer is to follow the guidance of the Holy Spirit. But in fact the Spirit works with the commandments (rules) of the New Testament in a perfectly compatible way.