Commenting on Habakkuk 2:4, John Calvin says this: “When the prophet says, ‘the just shall live by faith,’ the statement does not apply to impious and profane persons, whom the Lord by turning them to faith may justify, but the utterance is directed to believers and to them life is promised by faith. We must have this blessedness not just once (in justification) but must hold to it throughout life. To the very end of life believers have no other righteousness than that which is described as the free reconciliation with God by faith.”
Put another way, what Calvin is saying is that it’s not just justification, that one-time, forensic, legal declaration of “not guilty!” before God which is by faith. Rather, it’s the whole of the Christian life, from the moment of justification to the moment of death and then glorification which is by faith. Indeed, the sanctification of the believer is itself sola fide, by faith, in the same way that one is justified by faith.
So, I guess before we go too much further, we ought to somewhat clearly define what sanctification itself is. To my lights, the best way to think about sanctification is as the process of growth in holiness in the life of the believer from the moment of conversion to the moment of earthly death. It’s important to note though that this process of growth is wrought in the believer by the work of the Holy Spirit who indwells believers, a la 1 Corinthians 3:16
With that definition in mind, I think we can start to think through what exactly sanctification is theologically. I think any responsible talk about sanctification, at least in the life of the believer (or maybe especially in the life of the believer) really must start with what RC Sproul calls the chief human dilemma: God is holy, and we are not.
In the same vein as Sproul, Michael Allen says, “an evangelical account of the holy requires a steady focus upon the holiness of God, that is, the holiness of the inner triune life.” For Allen this is crucial, because it seems to be God’s holiness that He gives to us in Christ not only forensically in justification, but also transformatively in sanctification. We must, then, keep our eyes on God's holiness as He's revealed it in Scripture.
It doesn’t take much to call forth varied and sundry scriptural examples of God’s holiness. One thinks maybe first of Moses and the burning bush; a scene in which Moses is rebuked for wearing his shoes on holy ground, showing us that holy and profane cannot coexist together. The same sort of picture of God’s holiness becomes only more apparent as redemptive history progresses, for God’s people, Israel, are rebuked for their religious syncretism as they bring golden calves into the worship of God, mixing the holy and profane. Ours is a holy God, so much so that Israel cannot even touch the base of the mountain when Moses goes to speak with the Lord. What’s more, only the high priest can enter into the Holy of Holies, God’s abode. The populace at large is forbidden from God’s presence, as it were.
As we continue to read the Old Testament, it seems like one of the prevailing questions, not unrelated to Sproul’s observation, is how can a holy God commune with an unholy people? How can a sinless God look upon and interact with a sinful people? Of course, these questions are answered in the Person and Work of Jesus Christ, for it is His perfect life, death, and resurrection which render the believer justified before God and in the sending of the Holy Spirit, who comes to inhabit God’s people and sanctify them.
Sanctification rightly examined in a Reformed key must chart a course between moralism on one side and antinomianism on the other. Arising out of this sort of course charting seems to necessarily be the following questions: How good is good enough? How far do we need to progress in our personal holiness to be assured of the Holy Spirit’s work in our lives? I think, popularly articulated, the doctrine of sanctification has a tendency to result in a certain kind of navel-gazing which is maybe not so helpful for the average parishioner.
Ultimately, I think it’s best to follow a path not unlike that of Richard Lints and Michael Allen that sees sanctification as accomplished sola fide in addition to justification. It seems clear to me that GC Berkouwer is right when he refers to sanctification as “the constant commerce with the forgiveness of sins,” because whether the new convert is in mind, or Billy Graham is in mind, the Christian is never devoid of the tinge of sin in any good work (Is. 64:6). Thus, as the believer progresses through the Christian life, they must become more and more familiar with divine grace and divine forgiveness. But how might the believer continue to grasp hold of this divine grace? By none other than faith alone in Christ alone, a gift of God (Eph. 2:8). Thus, as Lints himself argues, “repentance rather than moral exertion is the appropriate response that flows from this faith."
I'll probably post on this again in the coming weeks as my ideas about sanctification begin to crystallize, but in the meantime, these are some of my preliminary thoughts.