In my last post, I outlined the ongoing debate between Dr. Lane Tipton and Dr. Michael Horton, in which the former has accused the latter of Lutheranism for asserting that the righteousness of Christ imputed in justification is the forensic basis of sanctification. Horton's thinking seems to be this: Since Christ purchased all saving benefits (including sanctification) by His law-satisfying "obedience unto death", and since the believer acquires interest in this satisfaction by imputation in his justification, then it follows that justification relates to sanctification as its forensic ground. This is not to deny that both justification and sanctification flow directly and efficaciously to the believer from union with Christ, but it is to affirm a certain forensic relationship between these benefits as they flow from union with Christ.
In any event, it appears that Dr. Tipton still maintains that the above-stated construction is distinctively Lutheran (if not Semi-Pelagian) and absolutely incompatible with Calvin's view that justification and sanctification are "distinct, inseparable, and simultaneous" benefits of union with Christ. Ironically enough, John Murray would appear to side with Horton (at least on this particular point). Hard to believe? Well, let's take a look at what the good Professor has to say.
In the following excerpt from his article, The Agency in Definitive Sanctification (Collected Writings, Vol. 2, pp. 286-287), Murray appears to take a both/and approach rather than Tipton's either/or response to Horton. In other words, although Murray wants to say that progressive sanctification is founded on much more than justification (namely, definitive sanctification), he nevertheless acknowledges Horton's thesis that "justification is the foundation of sanctification" as "doctrinally true." To be more precise, Murray agrees that justification gives the believer interest in Christ's legal satisfaction, which is the meritorious cause or purchase-price of all saving benefits (including sanctification). As such, justification "is the only proper relation on which a life of holiness can rest." Then, in addition to this (not over against it), he asserts that the efficacious cause or power-source of sanctification is union with Christ in His death and resurrection, such that the efficacy of sanctification is in no sense mediated through justification.
Now, we must ask: According to Dr. Tipton's definition, does this make Murray a Lutheran? You make the call!
No fact is of more basic importance in connection with the death to sin and commitment to holiness than that of identification with Christ in his death and resurrection. And this relation of Jesus' death and resurrection to the believer is introduced at this point in the development of Paul's gospel, be it noted, not with reference to justification but in connection with deliverance from the power and defilement of sin. So it is the relation to sanctification that is in the focus of thought. What then is this relation?
It might be said that the relation is that which justification sustains to sanctification, that the death and resurrection of Christ are directly the ground of our justification, that justification is the foundation of sanctification in that it establishes the only proper relation on which a life of holiness can rest, and that the relation of the death and resurrection of Christ to sanctification is this indirect one through the medium of justification. Or it might be said that by his death and resurrection Christ has procured every saving gift. The death and resurrection are therefore the meritorious and procuring cause of sanctification as well as of justification, and in this respect are as directly related to sanctification as to justification. All of this is doctrinally true and does not violate the analogy of biblical teaching.
But this analysis of the relation of the death and resurrection of Christ to sanctification does not do justice to Paul's teaching. He brings the death and resurrection of Christ into a much more direct relation to sanctification by way of efficiency and virtue than these foregoing proposals involve. The truth is that our death to sin and newness of life are effected in our identification with Christ in his death and resurrection, and no virtue accruing from the death and resurrection of Christ affects any phase of salvation more directly than the breach with sin and newness of life. And if we do not take account of this direct relationship we miss one of the cardinal features of New Testament teaching.