Over at TurretinFan's blog he just posted an exchange between a Cardinal and John Calvin, where Calvin allegedly soundly defeated the Cardinal in the span of a few paragraphs. However, as Calvin was teaching the Cardinal, he seems to have been ignorant of the true saving (Protestant) Gospel. This is a quote of what Calvin said to the Cardinal:
First, We bid a man begin by examining himself, and this not in a superficial and perfunctory manner, but to sift his conscience before the tribunal of God, and when sufficiently convinced of his iniquity, to reflect on the strictness of the sentence pronounced upon all sinners. Thus confounded and amazed at his misery, he is prostrated and humbled before God; and, casting away all self-confidence, groans as if given up to final perdition. Then we show that the only haven of safety is in the mercy of God, as manifested in Christ, in whom every part of our salvation is complete. As all mankind are, in the sight of God, lost sinners, we hold that Christ is their only righteousness, since, by his obedience, he has wiped off our transgressions; by his sacrifice, appeased the divine anger; by his blood, washed away our stains; by his cross, borne our curse; and by his death, made satisfaction for us. We maintain that in this way man is reconciled in Christ to God the Father, by no merit of his own, by no value of works, but by gratuitous mercy. When we embrace Christ by faith, and come, as it were, into communion with him, this we term, after the manner of Scripture, the righteousness of faith.
Here, Calvin is speaking on what takes place at Justification, more or less in line with what Scripture says. But, unknown to him, there is an essential part of justification that Calvin never knew about (and neither did Luther, it seems), and that is the doctrine of Christ's Active Obedience. In the Reformer's mind, Christ's Righteousness, by means of Christ's Obedience, resulted in the forgiving of sins. However, the later Calvinists denied this as heresy, stating not only is forgiveness of sins required, but also a "perfect law keeping" record as well.
Consider this analogy: If Adam started his life at "Level 0," he needed to keep the commandments perfectly to reach "Level +1" to be justified. Since he sinned, Adam took himself and all mankind to "Level -1". In Luther and Calvin's mind, Christ needed to forgive man's sin in order to take from from "Level -1" to "Level +1," but in the mind of later Calvinists, Christ's Cross only took man from "Level -1" to "Level 0." Man still needed Christ's perfect law keeping record transferred to their account to bring the "Level 0" to a "Level +1," just like Adam originally required. Clearly, this is two different Sola Fides, two different Gospels! In Calvin's Gospel, the Cross was sufficient; in the Gospel of most of Calvinism today and throughout history, the Gospel is that the Cross was insufficient. We know what Paul had to say about false Gospels (Gal 1:8).
Most Protestants are totally unaware that the Gospel their Seminaries and Pastors are teaching is "another Gospel," and indeed many think Calvin taught Active Obedience. See my Calvin & Active Obedience article or my John Calvin & Double Imputation article for more information.