Being justified by faith, we have peace with God.This whole doctrine is to be referred to that conflict of the terrified conscience, neither can it be understood apart from that conflict.Therefore inexperienced and profane men judge ill concerning this matter, who dream that Christian righteousness is nothing but civil and philosophical righteousness.
Heretofore consciences were plagued with the doctrine of works, they did not hear the consolation from the Gospel.Some persons were driven by conscience into the desert, into monasteries hoping there to merit grace by a monastic life.
Some also devised other works whereby to merit grace and make satisfaction for sins.Hence there was very great need to treat of, and renew, this doctrine of faith in Christ, to the end that anxious consciences should not be without consolation but that they might know that grace and forgiveness of sins and justification are apprehended by faith in Christ.
Men are also admonished that here the term "faith" does not signify merely the knowledge of the history, such as is in the ungodly and in the devil, but signifies a faith which believes, not merely the history, but also the effect of the history -- namely, this Article: the forgiveness of sins, to wit, that we have grace, righteousness, and forgiveness of sins through Christ.
Now he that knows that he has a Father gracious to him through Christ, truly knows God; he knows also that God cares for him, and calls upon God; in a word, he is not without God, as the heathen.For devils and the ungodly are not able to believe this Article: the forgiveness of sins.Hence, they hate God as an enemy, call not upon Him, and expect no good from Him.
Augustine also admonishes his readers concerning the word "faith," and teaches that the term "faith" is accepted in the Scriptures not for knowledge such as is in the ungodly but for confidence which consoles and encourages the terrified mind.