More particularly, is it the view of Calvin and of Reformed Orthodoxy that justification causes sanctification, or not? There seems to be some difference of opinion about this. Some detect the presence of causal language in the discussion of these questions by these theologians. And this seems to be sufficient to answer the question in the affirmative. Others stress the pivotal factor of union with Christ and of Christ’s double gift of justification and sanctification, and believe that this justifies answering the question in the negative, presumably on the grounds that there is no causal language visible at this point, and that there is symmetry between the two gifts.
What I have seen of the presentation of such opposing viewpoints suggests a certain amount of confusion, or at least a lack of exactness, among the parties. So though I do not want here to engage directly in attempting to answer the question, I think it may help to make some general remarks about causation. (For those who are curious about sources I refer to writers such as Mark A Garcia, Life in Christ (Paternoster, 2008) and John V. Fesko ‘Metaphysics and Justification in 16th and 17th Century Reformed Theology’, (Calvin Theological Journal, April 2011); and 'Peter Martyr Vermigli on Union With Christ and Justification', (Reformed Theological Review, April 2011). But as I say it is not my intention to engage directly with these chaps.) Instead we shall look particularly at Aristotelian four-fold causation to which Calvin and the RO were indebted (to one degree or another) in their endeavours to make justification and its relation to sanctification plain, as well as in other areas of theology.
Three or so points
1. In the Aristotelian four-fold causation schema – material, formal, efficient, and final – ‘cause’ is not used univocally. Calvin writes of these being different ‘kinds’ of causation, and so they are. (Inst. III.14.17) This ought to be kept in mind. It is best to think of these four ‘kinds’ of causation as providing different but compatible answers to the question ‘Why?’ Why is this a statue? Answer, because a sculptor made the sculpture (efficient cause); or because it is composed of sculptable material such as gold or clay or stone, and not of frogspawn or tissue paper (material cause); because it has the form of a statue and not of a bar of gold (formal cause); because it was the intention of its maker to create a statue (final cause) and not a gold chain. Each these answers the ‘Why?’ question differently, each answer complements the other answers. Which answer is offered or discussed would depend upon the interests of one asking the question. Additionally, the sculptor’s tools may be thought of as the ‘instrumental’ cause, a term made famous in Reformed theology by Calvin and others (including the Westminster Confession) who refer to faith as the instrumental cause of justification. So the four causes refer to different features of a complex situation, not to a case in which X causes Y which in turn causes z, three efficient causes, like the falling of a line of dominoes or the shunting of wagons in an (old fashioned?) railway yard. Even if justification may not be the efficient cause of sanctification, perhaps it is its cause in some of the sense? (There's the additional factual question of whether this four-fold scheme is ever applied to the justification-sanctification distinction.)
2. This schema, according to Aristotle, when we see it operate in the physical world, does not do so infallibly, but only ‘for the most part’; acorns produce oaks, but occasionally there is a sport, or a mutation; lions beget lion cubs, but occasionally such cubs are born de-formed; there are Siamese twins, and so on. And in the case of our sculptor, his skill may not be very great and though intending a masterpiece the result of his efforts may be a botch. Clearly when the language of Aristotelian causality is used of divine activity, recognition must be given to divine power and wisdom. No sports or deformities or failures in intention here. So whereas in the physical world there is a contingent relation between an efficient cause and its effect, even if we were to suppose that sanctification is an effect of justification that effect may be necessarily, or certainly unfailingly connected.
But is justification the efficient cause of sanctification? It is hard to see that it is or could be, at least in the Pauline-Augustinian outlook of the Reformers, according to which every step of salvation is due to the unmerited, efficaciously powerful grace and mercy of God. The associated question, Could there be justification without sanctification? seems to be unnecessarily speculative. They are held together at least by the divine decree that this be so, and so are connected by at least a hypothetical or conditional necessity, and may even be intrinsically connected. So the fear that if causal categories are applied to justification and sanctification they may come apart, that justification may fail to bring about sanctification, would appear to be groundless.
3. The question, Could justification be the cause of sanctification? is also ambiguous regarding the sense in which justification and sanctification are being taken. For each word may refer either to an effect; the event of coming to be justified, which is instrumentally caused by faith; or it could refer to the state of being justified. Most likely, in the claim that justification is the cause of sanctification, justification is being referred to as a state, the state of being justified. But can a state be a cause in the sense of any of the four Aristotelian ways? If the question raised in this area is, does justification cause good works? then this presumably refers to the act or acts of reliance on Jesus. Can the state of being justified bring about sanctification? Sounds weird. But ‘sanctification’ has a similar ambiguity: it also may mean the event of becoming sanctified, or the state of being sanctified. Which?
Faith along with hope and love form a small constellation of Spirit-given virtues. So that faith, even considered as the instrumental cause of justification, is a subjective grace of the Spirit, and so a sanctifying fruit, and inseparable from other Christian virtues. If we are not to get into a further tangle at this point we need some further distinctions. (I have discussed the point briefly, with the expert assistance of Francis Turretin, in ‘Word and Spirit in Conversion’ inSpirit of Truth and Love, Studies in Christian Doctrine and Experience, ed. David F. Wright (Edinburgh, Rutherford House, 2007, 129-31)).
It is hard to see where the Reformed theologians cited earlier teach that justifying faith gives rise (even instrumentally) to hope and love. Certainly, faith works by love: it is the combining of the graces of saving faith, relying on the promises of God, and love to God and neighbour, shed abroad in our hearts, as Paul puts it, that lead to good works. So if we are going to see some light in this area, a bit more sorting out needs to be done.
And why, in any case, is there an opposition made between ‘causal language’ and Calvin’s language about union with Christ and the two distinct but inseparable gifts of justification and sanctification? As does the Johannine language of the vine and its fruit. Does all this not look like causal language as well? [We must be careful not to fall into the mistaken of thinking that it’s a condition of language being causal that the term ‘causal’ or its family members are used.] If union with Christ is the source of good works, does this not mean that the union is the cause of the good works? I suspect once the necessary sorting out has been done, there won’t be a hairsbreadth between the language of union with Christ and ‘causal language’.
But there is a weaker sense of ‘cause’ in which we find the Reformed theologians in the 16th and 17th centuries writing of the connection between faith and works in which ‘cause’ simply and loosely means ‘condition’. If we refer again briefly to the four-fold causation schema, then any of these may be said to be a cause in the sense that each is a necessary condition for the achieving of causation in its full, four-fold sense. So in this sense faith may be said to be a necessary condition of good works. Without faith, no good works. So there is a close connection between faith and good works, an indispensable connection, but this does not entail that the saving faith, the faith which justifies, is an efficient cause of sanctification. Though of course it does not rule it out either.
My thought is that if due regard is paid to the peculiarities of the Aristotelian schema and its transposition to the arena of divine activity, there are perfectly good senses in which one might say both that justification and sanctification are the twin fruits [causal effects?] of the duplex gratia which flows from union with Christ, and that justification is the cause of sanctification, its necessary precondition. But not, merely for this reason, an efficient cause of sanctification.