Since then this faith can reign only in the inward man, as it is said, "With the heart man believeth unto righteousness" (Rom. x. 10); and since it alone justifies, it is evident that by no outward work or labour can the inward man be at all justified, made free, and saved; and that no works whatever have any relation to him. And so, on the other hand, it is solely by impiety and incredulity of heart that he becomes guilty and a slave of sin, deserving condemnation, not by any outward sin or work. Therefore the first care of every Christian ought to be to lay aside all reliance on works, and strengthen his faith alone more and more, and by it grow in the knowledge, not of works, but of Christ Jesus, who has suffered and risen again for him, as Peter teaches (1 Peter v.) when he makes no other work to be a Christian one. Thus Christ, when the Jews asked Him what they should do that they might work the works of God, rejected the multitude of works, with which He saw that they were puffed up, and commanded them one thing only, saying, "This is the work of God: that ye believe on Him whom He hath sent, for Him hath God the Father sealed" (John vi. 27, 29). Hence a right faith in Christ is an incomparable treasure, carrying with it universal salvation and preserving from all evil, as it is said, "He that believeth and is baptised shall be saved; but he that believeth not shall be damned" (Mark xvi. 16). Isaiah, looking to this treasure, predicted, "The consumption decreed shall overflow with righteousness. For the Lord God of hosts shall make a consumption, even determined (verbum abbreviatum et consummans), in the midst of the land" (Isa. x. 22, 23). As if he said, "Faith, which is the brief and complete fulfilling of the law, will fill those who believe with such righteousness that they will need nothing else for justification." Thus, too, Paul says, "For with the heart man believeth unto righteousness" (Rom. x. 10). But you ask how it can be the fact that faith alone justifies, and affords without works so great a treasure of good things, when so many works, ceremonies, and laws are prescribed to us in the Scriptures? I answer, Before all things bear in mind what I have said: that faith alone without works justifies, sets free, and saves, as I shall show more clearly below. Meanwhile it is to be noted that the whole Scripture of God is divided into two parts: precepts and promises. The precepts certainly teach us what is good, but what they teach is not forthwith done. For they show us what we ought to do, but do not give us the power to do it. They were ordained, however, for the purpose of showing man to himself, that through them he may learn his own impotence for good and may despair of his own strength. For this reason they are called the Old Testament, and are so.