+III. If the promise might be disannulled, the law could not do it.+--1. The promise, or covenant, was made with Abraham, and continued by God four hundred and thirty years before the law was given. 2. If the law abolish the promise, then the inheritance must come by the law. But that cannot be. If the inheritance of eternal life be by the law, it is no more by the promise. But it is by the promise, because God gave it unto Abraham freely by promise; therefore, it comes not by the law. This giving was no private but a public donation. That which was given to Abraham was in him given to all that should believe as he did.--_Perkins._ Vers. 15-17. _Divine and Human Covenants._ I. A covenant, as between man and man, is honourably binding (ver. 15). II. The Divine covenant made to Abraham ensures the fulfilment of promises to all who believe as Abraham did (ver. 16). III. The law cannot abrogate the Divine covenant of promise (ver. 17). Ver 18. _Law and Promise._--1. So subtle is the spirit of error that it will seem to cede somewhat to truth, intending to prejudice the truth more than if it had ceded nothing. The opposers of justification by faith did sometimes give faith some place in justification and pleaded for a joint influence of works and faith, of law and promise. 2. The state of grace here and glory hereafter is the inheritance of the Lord's people, of which the land of Canaan was a type. There are only two ways of attaining a right to this inheritance--one by law, the other by promise. 3. There can be no mixture of these two, so that a right to heaven should be obtained partly by the merit of works and partly by faith in the promise. The only way of attaining it is by God's free gift, without the merit of works.--_Fergusson._ _MAIN HOMILETICS OF THE PARAGRAPH.--Verses_ 19, 20. _The Inferiority of the Law._ +I. It did not justify but condemn the sinner by revealing his sin.+--"It was added because of transgressions" (ver. 19). Law has no remedial efficacy. It reveals and emphasises the fact of sin. It has no terror while it is obeyed. When it is violated then it thunders, and with pitiless severity terrifies the conscience and inflicts unsparing punishment. There is no strain of mercy in its voice, or in the inflexibility of its methods. It surrenders the condemned to an anguish from which it offers no means of escape. It is said that, after the murder of Darnley, some of the wretches who were concerned in it were found wandering about the streets of Edinburgh crying penitently and lamentably for vengeance on those who had caused them to shed innocent blood.