But Sarah, which denotes the state of the gospel, that new city which Christ hath brought from heaven with him (see note [b] Rev. xxi.), of which all we Christians are free-men or citizens, she is a freewoman, and signifies that we Christians, Gentiles as well as Jews, are free from the Mosaical rites, &c., and that we may be justified without them. According to that prophecy, Isa. liv. 1, Rejoice &c. the meaning of which is, that the gospel covenant, which when Christ was here on earth had few children, few that were brought forth by it, after his death, upon the preaching of the gospel by the apostles to the Gentiles, had many more than among the Jews in his lifetime. But, my brethren, as Isaac was born only by strength of God's promise, not by any ordinary means, Abraham and Sarah being beyond age, so are the children of God received to be such, and justified only by the promise of God, (that is, through the strength of that promise to Abraham and covenant in Christ, that all faithful, obedient, persevering believers should be justified,) without any Mosaical performances.