This is a very important term to be perfectly understood, from being the very character of our Lord Jesus Christ, who became the Surety for his church and people. It was an antient custom among the Hebrews to admit of a surety or sponsor for each other. Thus, if a man became bound for another, he was called his surety. And it should seem to have been the method upon all these occasions, that when one became responsible for another, he struck hands with the creditor. We find Judah pledging himself as a surety to his Father for his brother Benjamin. (Genesis 43:8) And Job and, Solomon both take notice of the same, under the article of suretyship. (See Job 17:3; Proverbs 6:1-2) But I should not have thought it necessary to have introduced the subject in this place, had it not been with a view to have brought the reader into a more intimate acquaintance with the nature of a surety as it concerns the person of our Lord Jesus Christ. Here the matter becomes so abundantly interesting, that it merits the closest regard of his people.
The Holy Ghost by his servant the apostle Paul, hath informed the church that Jesus "was made surety of a better testament," that is the testament or covenant of redemption by Christ's blood. (Hebrews 7:22) By which we understand that in the antient settlement of eternity, the Lord Jesus Christ stood up at the call of his Father, the covenant Head and Surety of his people, to answer both for their debt and their duty. So that he stood in their law, room, and stead, in all he did and suffered, and it was covenanted and agreed upon by the Almighty Covenanters, that all Jesus did and suffered should be put to their account. This is the idea of a surety, and Christ was precisely this. So that when he had fulfilled all righteousness, and by his spotless sacrifice had done away all the penal effects of sin, his people were to all eternity and purposes, righteous in his righteousness, and free from all sin in his blood. Such is the idea of a surety considered with an eye to Christ. Blessed are they who are interested in it, and who no longer seek for justification but in him who is made the Surety of a better testament than the old covenant of a man's own works. All of this description find the blessedness of being accepted in the Suretyship of the Lord Jesus, and can join the prophet's declaration: "Surely shall one say, In the Lord have I righteousness and strength: even to him shall men come, and all that are incensed against him shall be ashamed. In the Lord shall all the seed of Israel be justified, and shall glory." (Isaiah 45:24-25)