The Ground of Justification

"The ground of our justification, therefore, is that God reconciles us to himself, from regard not to our works, but to Christ alone, and, by gratuitous adoption, makes us, instead of children of wrath, to be his own children. So long as God looks to our works, he perceives no reason why he ought to love us. Wherefore, it is necessary to bury our sins, and impute to us the obedience of Christ (because [his is] the only obedience which can stand his scrutiny), and adopt us as righteous through his merits. This is the clear and uniform doctrine of scripture, "witnessed," as Paul says, "by the law and the prophets" (Rom. 3:21); and so explained by the gospel, that a clearer law cannot be desired. Paul contrasts the righteousness of the law with the righteousness of the gospel, placing the former in works, and the latter in the grace of Christ (Rom. 10:5, etc.). He does not divide it into two halves, giving works the one, and Christ the other; but he ascribes it to Christ entirely, that we are judged righteous in the sight of God."

John Calvin. The Necessity of Reforming the Church