Romans 10

Rom. 10:3. "For they being ignorant of God's righteousness, and going about to establish their own righteousness, have not submitted themselves unto the righteousness of God." The reason why the righteousness of Christ, from time to time, is called by the name of God's righteousness, may probably be this, that the grand difference between the righteousness of the two covenants is this, that one is a mere human righteousness, the other is a Divine righteousness, or the righteousness of a Divine Person; and not that one is our own personal righteousness, and the other the righteousness of Another that is our surety. For if Adam had stood, and we had been justified as in the way of the first covenant, we that are the posterity of Adam should not have been justified by our own personal righteousness, but should have been justified as much by the righteousness of another as now under the second covenant. God, in infinite wisdom, hath so ordered things to bring mankind to a greater dependence on God, that mankind should not be justified by their own righteousness, that is, by the righteousness of mankind, but by the righteousness of God, that they should have their happiness, their strength, their wisdom, and their righteousness, and their all in God, that God might not only be the sum of their objective good or good of enjoyment (but) so (that) He should be the sum of their glory or good of excellency, recommending them to that objective good, and so that God should be all in all: as there is a great disposition in man to seek his good in the creature, and to keep at a distance from God, and in opposition to that universal union and dependence on God which is the aim of the gospel, so there is a strong inclination in men to acquit themselves of guilt, and trust in a mere human righteousness and reject the righteousness of God. That this is the reason why Christ's righteousness is called God's righteousness - viz., to set it in a more clear opposition to the righteousness of men - is confirmed from the antithesis in Romans 1:17; Romans 1:18, "For therein is the righteousness of God revealed from faith to faith: as it is written, The just shall live by faith. For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men, who hold the truth in unrighteousness." Here the righteousness of God is set in opposition to the unrighteousness of men, and that is implied why the righteousness of One that is above men, the righteousness of God is necessary, because the righteousness of men or a mere human righteousness is insufficient, or because men have no righteousness or there is no human righteousness. This confirms that the righteousness we are justified by is called the righteousness of God - viz., to set it in the clearer opposition to the righteousness of the first covenant, which is the righteousness of mankind. The righteousness that Christ provided is properly called the righteousness of God, in opposition to the human righteousness of the first covenant, on the following accounts - (1.) That whereas the righteousness of the first covenant was a mere human righteousness, this is a righteousness of a Person infinitely above a mere human person, it is the righteousness of a Divine Person; (2.) It is from His divinity that it derives its value whereby it is sufficient to justify us, and so is fit to succeed in the room of that human righteousness which we have failed of; it is as it is the righteousness of God, that it is of any avail to our justification; (3.) As the righteousness of the first covenant was in man wrought out by man, we have this righteousness not by our works, but wholly and immediately of God, by His gift and imputation, when we have none wrought by us or inherent in us.

The Apostle by God's righteousness means the righteousness that a Divine Person hath or is the subject of, and is given to believers; and, by God's rest, the same Apostle means the rest which God or Christ hath, and is also given to believers. Hebrews 4:5.

Rom. 14:15