Hebrews 6:10

10.For God is not unrighteous, etc. These words signify as much as though he had said, that from good beginnings he hoped for a good end.

But here a difficulty arises, because he seems to say that God is bound by the services of men: “I am persuaded,” he says, “as to your salvation, because God cannot forget your works.” He seems thus to build salvation on works, and to make God a debtor to them. And the sophists, who oppose the merits of works to the grace of God, make much of this sentence, “God is not unrighteous.” For they hence conclude that it would be unjust for him not to render for works the reward of eternal salvation. To this I briefly reply that the Apostle does not here speak avowedly of the cause of our salvation, and that therefore no opinion can be formed from this passage as to the merits of works, nor can it be hence determined what is due to works. The Scripture shows everywhere that there is no other fountain of salvation but the gratuitous mercy of God: and that God everywhere promises reward to works, this depends on that gratuitous promise, by which he adopts us as his children, and reconciles us to himself by not imputing our sins. Reward then is reserved for works, not through merit, but the free bounty of God alone; and yet even this free reward of works does not take place, except we be first received into favor through the kind mediation of Christ.

We hence conclude, that God does not pay us a debt, but performs what he has of himself freely promised, and thus performs it, inasmuch as he pardons us and our works; nay, he looks not so much on our works as on his own grace in our works. It is on this account that he forgets not our works, because he recognizes himself and the work of his Spirit in them. And this is to be righteous, as the Apostle says, for he cannot deny himself. This passage, then, corresponds with that saying of Paul, “He who has begun in you a good work will perfect it.” (Philippians 1:6.) For what can God find in us to induce him to love us, except what he has first conferred on us? In short, the sophists are mistaken in imagining a mutual relation between God’s righteousness and the merits of our works, since God on the contrary so regards himself and his own gifts, that he carries on to the end what of his own goodwill he has begun in us, without any inducement from anything we do; nay, God is righteous in recompensing works, because he is true and faithful: and he has made himself a debtor to us, not by receiving anything from us; but as Augustine says, by freely promising all things. (101)

And labor of love, etc. By this he intimates that we are not to spare labor, if we desire to perform duty towards our neighbors; for they are not only to be helped by money, but also by counsel, by labor, and in various other ways. Great sedulity, then, must be exercised, many troubles must be undergone, and sometimes many dangers must be encountered. Thus let him who would engage in the duties of love, prepare himself for a life of labor. (102)

He mentions in proof of their love, that they had ministered and were still ministering to the saints. We are hence reminded, that we are not to neglect to serve our brethren. By mentioning the saints, he means not that we are debtors to them alone; for our love ought to expand and be manifested towards all mankind; but as the household of faith are especially recommended to us, peculiar attention is to be paid to them; for as love, when moved to do good, has partly a regard to God, and partly to our common nature, the nearer any one is to God, the more worthy he is of being assisted by us. In short, when we acknowledge any one as a child of God, we ought to embrace him with brotherly love.

By saying that they had ministered and were still ministering, he commended their perseverance; which in this particular was very necessary; for there is nothing to which we are more prone than to weariness in well­doing. Hence it is, that though many are found ready enough to help their brethren, yet the virtue of constancy is so rare, that a large portion soon relax as though their warmth had cooled. But what ought constantly to stimulate us is even this one expression used by the apostle, that the love shown to the saints is shown towards the name of the Lord; for he intimates that God holds himself indebted to us for whatever good we do to our neighbors, according to that saying,

“What ye have done to one of the least of these,
ye have done to me,” (Matthew 25:40;)

and there is also another,

“He that giveth to the poor lendeth to the Lord.”
(Proverbs 19:17.)

The word ἄδικος, unrighteousness, is rendered by many, unmerciful or unkind. But the reason for such a meaning is this: There are three kinds, we may say, of righteousness — that of the law, of love, and of promise. To act according to the law is to be righteous; to comply with what love requires, that is, to be kind and charitable, is to be righteous, and hence almsgiving is called righteousness has often the meaning of faithfulness or mercy. See 1 John 1:9. Therefore the meaning here is, that God is not so unrighteous as not to fulfill his promise. Hence the notion of merit is at once shown to be groundless. — Ed