De natura et gratia libri III, cum Apologia contra Catharinum

By this reason, therefore, to justified men, whether they have preserved the grace received perpetually, or recovered what was lost, the words of the Apostle are to be set forth: Abound in every good work, knowing that your labour is not in vain in the Lord. For God is not unjust, that he should forget your work and the love which you have shown in his name, and do not lose your confidence, which has a great reward. And therefore to those who do good even to the end, and hope in God, eternal life is to be set forth, both as a grace mercifully promised to the sons of God through Christ Jesus, and as a reward from the promise of God himself, to be faithfully rendered to their good works and merits. For this is that crown of justice which the Apostle said was laid up for him after his struggle and course, to be rendered to him by the just judge. But not only to him, but also to all who love his coming. For since Christ Jesus himself, as head into members, and as the vine into branches, continually pours into the justified themselves a power which always precedes, accompanies and follows their good works, and without which they could by no means be pleasing and meritorious to God, nothing more is to be believed to be wanting to the justified themselves, so that they may be considered to have fully satisfied with those works which are done in God according to the divine law, for the state of this life, and truly to have merited eternal life to be obtained also in its own time (if only they depart in grace), since Christ our Saviour says, If anyone drinks of the water which I shall give him, he shall not thirst for ever. But it shall become in him a fountain of living water, springing up unto eternal life. Thus neither is our own justice established as if it were our own from ourselves, nor is the justice of God ignored or repudiated: for the justice which is called ours, because through it inherent in us we are justified, is the same justice of God, because it is infused into us by God through the merit of Christ. Nor is that to be omitted, that although good works are attributed in the sacred Scriptures to such a degree that even to him who gave a cup of cold water to one of his least ones Christ promises that he shall not lose his reward, and the Apostle testifies that what is at present momentary and light in our tribulation works in us an eternal weight of glory above measure in sublimity. Yet far be it that a Christian man should either trust or glory in himself, and not in the Lord, whose goodness is so great towards all men that he wills to be their merits which are his gifts. And because we all offend in many things, each one, as he ought to have mercy and goodness, so also severity and judgment before his eyes, nor should anyone judge himself even if he is conscious of nothing, since the whole life of men is to be examined and judged not by human judgment, but by God's: who will illuminate the hidden things of darkness, and will manifest the counsels of hearts, and then praise shall be to each one from God, who (as it is written) will render to each one according to his works.

After this catholic doctrine of justification, which unless each one has faithfully and firmly received, he cannot be justified: it pleased the holy Synod to subjoin these canons, so that all may know not only what they ought to hold and follow, but also what they ought to avoid and flee.