Blog 129: 3.14.12 - 3.14.18
Calvin borrowed generously from earlier theologians (especially Augustine) in formulating his Institutes of the Christian Religion. Of one group, though, he was especially critical: "the Schoolmen," also known as "the Scholastics."
The Schoolmen were theologians who taught theology and philosophy at major European universities during the Middle Ages--men like William of Ockham, Duns Scotus, and especially Thomas Aquinas. Although Calvin valued the scholarship of these theologians, he tended to be critical of their theology, especially as it pertained to the grace of God.
Generally speaking, the Schoolmen conceded that human righteousness was not, in and of itself, worthy to gain salvation. Nevertheless, they believed that good works which went above and beyond the call of duty (works of "supererogation") could merit forgiveness for sinners.
Calvin rejected this argument outright. The only righteousness perfect enough to justify a sinner before God is the righteousness of Jesus Christ, received by faith. Only a sinner clothed in the innocence of Christ has continual forgiveness before God.
The error of the Schoolmen, from Calvin's perspective, was their failure to take sin as seriously as God takes it. If they truly understood how execrable it is to sin against a holy God, they would never pretend that the sum of a sinner's righteousness could ever compensate for even one little sin.
Nor did the Schoolmen truly understand the obedience that God requires. Jesus said that even if we were to do everything that God commands, we would still be nothing more than "unworthy servants" (Luke 17:10). Therefore, we should neither trust in the merit of our works nor ascribe to them any boastful glory, as the Schoolmen did.