The following is from John Calvin’s Reply to Sadoleto.
You, in the first place, touch upon justification by faith, the first and keenest subject of controversy between us. Is this a knotty and useless question? Wherever the knowledge of it is taken away, the glory of Christ is extinguished, religion abolished, the church destroyed, and the hope of salvation utterly overthrown. That doctrine, then, though of the highest moment, we maintain that you have nefariously effaced from the memory of men. Our books are filled with convincing proofs of this fact, and the gross ignorance of this doctrine, which even still continues in all your churches, declares that our complaint is by no means ill-founded. But you very maliciously stir up prejudice against us, alleging that by attributing everything to faith, we leave no room for works…
First, we bid a man begin by examining himself, and this not in a superficial and perfunctory manner, but to cite 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 sins; 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.
What have you here, Sadoleto, to bite or carp at? Is it that we leave no room for works? Assuredly we do deny that in justifying a man they are worth one single straw. For Scripture everywhere cries aloud, that all are lost; and every man’s own conscience bitterly accuses him. The same Scripture teaches that no hope is left bu int the mere goodness of God, by which sin is pardoned, and righteousness imputed to us. It declares both to be gratuitous, and finally concludes that a man is justified without works (Rom 4:7). But what notion, you ask, does the very term righteousness suggest to us if respect is not paid to good works? I answer, if you would attend to the true meaning of the term justifying in Scripture, you would have no difficulty. For it does not refer to a man’s own righteousness, but to the mercy of God, which contrary to the sinner’s deserts, accepts of a righteousness for him, and that by not imputing his unrighteousness. Our righteousness, I say, is that which is described by Paul (2 Cor 5:19) that God hath reconciled us to Himself in Jesus Christ. The mode is afterwards subjoined – by not imputing sin. He demonstrates that it is by faith only we become partakers of that blessing, when he says that the ministry of reconciliation is contained in the gospel. But faith, you say, is a general term, and has a larger signification. I answer that Paul, whenever he attributes to it the power of justifying, at the same time restricts it to a gratuitous promise of the divine favor, and keeps it far removed from all respect to works. Hence his familiar inference – if by faith, then not by works. On the other hand – if by works, then not by faith.
But, it seems, injury is done to Christ, if, under the pretense of His grace, good works are repudiated, He having come to prepare a people acceptable to God, zealous of good works, while to the same effect, are many similar passages which prove that Christ came in order that we, in doing good works, might, through Him, be accepted by God. This calumny, which our opponents have ever in their mouths, viz., that we take away the desire of well-doing from the Christian life by recommending gratuitous righteousness, is too frivolous to give us much concern. We deny that good works have any share in justification, but we claim full authority for them in the lives of the righteous. For if he who has obtained justification possesses Christ, and at the same time, Christ never is where His Spirit is not, it is obvious that gratuitous righteousness is necessarily connected with regeneration. Therefore, if you would duly understand how inseperable faith and works are, look to Christ, who, as the Apostle teaches (1 Cor 1:30) has been given to us for justification and for sanctification. Wherever, therefore, that righteousness of faith, which we maintain to be gratuitous, is, there too Christ is, and where Christ is, there too is the Spirit of holiness, who regenerates the soul to newness of life. On the contrary, where zeal for integrity and holiness is not in vigor, there neither is the Spirit of Christ nor Christ Himself; and wherever Christ is not, there is no righteousness, nay there is no faith; for faith cannot apprehend Christ for righteousness without the Spirit of sanctification.