Some background is necessary. Sola Fide is the Protestant doctrine that through faith the sinner is formally credited with Christ's Righteousness, this takes place at Justification (where God legally declares the individual to be in good legal standing before Him). This Righteousness consists of two components, popularly termed Christ's "active obedience" and "passive obedience." The "active obedience" consists of Christ's perfect obedience to the Law, while the "passive obedience" consists of Christ's suffering the full punishment due to your sins.
Luther famously referred to this situation as the "Great Exchange," where Christ's perfect obedience to the Law was credited to your sinful account (making your account look as if you had been perfectly obedient), while your sin and guilt was credited to Christ's sinless account (who then received the punishment due, though He was never personally guilty of sin). That's Sola Fide in a nutshell.
While Catholics dogmatically reject the above description, because we don't believe it is found in Scripture, that is not the topic of this post.
Just when I thought I had see all the various definitions of Sola Fide, I came across a blog advocating something I never imagined. This blog was run by a Calvinist who denied the imputation (crediting) of the "active obedience" of Christ. I invite you to check out the link and especially read the brief (but very insightful) articles he wrote and linked to. He does not deny Christ lived a life of perfect obedience, that is a common misunderstanding, he simply denies this life of perfect obedience to the Law is imputed to the sinner and thus has no role in the sinner's Justification.
This Calvinist alleges that there were disputes early on in the Reformation, especially in England, where Protestants could not agree on whether or not Christ's active obedience played a role in justification. (There was no dispute regarding Christ's passive obedience, all sides agreed it played a role in justification.) This dispute was especially brought out in the drafting up of two major Protestant confessions, the Anglican 39 Articles and the Westminster Confession. The "Majority" crowd held that Christ's active obedience did play a role in justification, while the "Minority" crowd denied this. This Calvinist states that historical records show that a compromise was reached when these Confessions were drafted, the areas talking about justification would be deliberately stated vaguely enough that both the Majority and Minority view would be acceptable.
I looked up both Confessions myself, and I can see how this would be possible, though I have to admit sometimes the wording seems to favor the Majority view. However, what really convinced me that the wording was deliberately vague is when I looked up what the London Baptist Confession (1689) had to say. The LBC basically took the Westminster Confession (1646), word for word, and made slight modifications towards the Baptist view (e.g. the Westminster commanded infant baptism while the LBC explicitly denied it). One of the modifications, which I never noticed before, was very subtle but clearly no accident. Compare the Westminster and LBC on their chapters regarding justification:
Westminster Ch 11: I. Those whom God effectually calleth, he also freely justifieth: not by infusing righteousness into them, but by pardoning their sins, and by accounting and accepting their persons as righteous; not for anything wrought in them, or done by them, but for Christ's sake alone; not by imputing faith itself, the act of believing, or any other evangelical obedience to them, as their righteousness; but by imputing the obedience and satisfaction of Christ unto them, they receiving and resting on him and his righteousness by faith; which faith they have not of themselves, it is the gift of God.Notice how the wording is virtually identical until this last point. It is especially significant that the LBC explicitly made the distinction between active obedience and passive obedience, where as the WC did not. This to me is clear evidence that there was such a dispute and that the WC was deliberately vague on this point.
London Baptist Ch 11: 1. Those whom God effectually calls, he also freely justifies, not by infusing righteousness into them, but by pardoning their sins, and by accounting and accepting their persons as righteous; not for anything wrought in them, or done by them, but for Christ's sake alone; not by imputing faith itself, the act of believing, or any other evangelical obedience to them, as their righteousness; but by imputing Christ's active obedience unto the whole law, and passive obedience in his death for their whole and sole righteousness by faith, which faith they have not of themselves; it is the gift of God.
What I as a Catholic find fascinating about the Minority view is how much I agree with it's reasoning for rejecting the concept of active obedience. The Scriptures simply nowhere state that Christ lived a life of perfect obedience to the Law in our place. The Minority view is adamant and sees the few texts popularly given as evidence (e.g. Romans 5:19) as simply falling well short of evidence for active obedience, especially in key contexts discussing justification (e.g. they point out Romans 3:21-26 is concerned only with Christ's death, with no mention of active obedience). The main difficulty I see for the Minority view, looking at this as if I were Protestant, is how they explain Adam was justified since active obedience is not required and he obviously didn't need sins forgiven. From a Catholic perspective, the main problem remaining with the Minority view is that it affirms Christ's passive obedience (suffering and death) came in the form of Penal Substitution - which is a view of the Atonement which Catholics deny as unBiblical (see my Penal Substitution debate for more information).
Not only is this fascinating to me, but I believe it is a hopeful sign of a future reconciliation of Protestantism back to the Catholic Church, because the Minority view is in many ways "halfway" there (considering, as Luther put it, Sola Fide is the doctrine by which the Church stands or falls). While I've always been aware of the Majority view, I see the Minority view as a way of building a sort of bridge because "half" of the definition of Sola Fide has been addressed.
A final but very relevant point, though I don't think needs to be discussed too much at the present moment, is to note how Sola Scriptura failed in this regard to lead two groups of Christians to agree on what "the truth" was, and how Sola Scriptura ultimately cannot settle disputes like this. From a Catholic perspective, to deny Christ's active obedience is a huge blow to Sola Fide, because to deny it effectively refutes Sola Fide for the (great) Majority of Protestants (especially Calvinists and Lutherans).