Such faith and trust in the mercy of God are extolled, particularly in the Prophets and Psalms, as the highest and the most holy worship of God. For although the law does not, like the Gospel, chiefly preach grace and the remission of sin, yet the promises respecting the coming Christ were handed down from one Patriarch to the other, and they knew and believed, that God would give blessings, grace, comfort, and salvation, through Christ, the blessed seed. Hence, if they understood that Christ was to be the treasure, paying for our sins, they knew that our works could never pay off so great a debt. They therefore received grace, salvation, and remission of sin, without any merit, and were saved through faith in the divine promises and the Gospel of Christ, as well as we, or the saints in the New Testament.

Hence the frequent repetition of the words mercy, goodness, faith, in the Psalms and Prophets; as, in Psalms 130:3–6; “If thou, LORD, shouldst mark iniquities, O LORD, who shall stand?” Here David confesses his sins, and boasts of no merit; but continues:“But there is forgiveness with thee, that thou mayest be feared.” Now he is comforted again, relies on grace and mercy, trusts in the divine promises, and says: “My soul waiteth for the Lord, and in his word do I hope.” And again:“My soul waiteth on the Lord;” that is, as thou hast promised forgiveness of sin, I will hold to thy word; I will trust and rely upon thy gracious promises.   (Henkel Translation, p. 167-168).

Therefore, when we speak of justifying faith, (fide justificante,) it includes first, the divine promises; secondly, that they offer grace freely and without our merit; thirdly, that the blood of Christ and his merits are the treasure which atones for our sins. The promises are received through faith; but as they offer grace without merit, all our worthiness and merit fall to the ground, and grace and boundless mercy alone are praised. The merit of Christ is the treasure; for that must indeed be a treasure and a noble pledge, which pays for the sins of the whole world. All the Scriptures, of the Old and New Testaments, when speaking of God and faith, often use the expressions—goodness, mercy; and in all their writings the holy Fathers teach, that we are saved by grace, goodness, and forgiveness.

Now whenever we find the word mercy in the Scriptures, or in the writings of the Fathers, we must remember, that it refers to faith, which embraces the promise of such mercy.

Again, whenever the Scriptures speak of faith, they mean the faith which is based upon grace alone. For faith does not justify us before God, as though it were in itself our work, and our own, but solely because it receives the grace; promised and offered without merit and presented out of the rich treasures of mercy. (Henkel Translation, p. 167).