3:16 Now to Abraham and his seed were the promises made. He saith not, And to seeds, as of many; but as of one, And to thy seed, {18} which is {l} Christ.
(18) He puts forth the sum of the seventh argument, that is, that both the Jews and the Gentiles grow together in one body of the seed of Abraham, in Christ alone, so that all are one in Christ, as it is afterward declared in Ga 3:28.
(l) Paul does not speak of Christ's person, but of two peoples, who grew together in one, in Christ.
3:16 Now to Abraham and his seed were the promise made. The covenant with its promises was made with Abraham and his seed. There were promises spoken on several occasion. See Ge 12:3,7 13:16 15:05 17:07 The promises of the covenant were to the seed, as well as to Abraham, and hence did not terminate with his death.
He saith not, And to seeds, as of many, but... to thy seed. This passage has excited much criticism. Many have thought that Paul made a grammatical mistake. Even Luther says:
My dear brother Paul, this argument won't stick.''
The criticism is that sperma, the Greek word rendered seed, is a collective noun and may include all Abraham's descendants. Paul elsewhere (Ro 4:18 9:7) shows that he knew just the meaning of sperma, but the question here is not one of grammar, but of spiritual meaning. Paul does not mean that sperma ( seed ) excludes plurality, but that it implies unity. Not the word children or descendants is used. This would embrace the children of Ishmael, of Esau, and of Keturah. But there is a seed to whom the promise is given; a seed that embraces many, but is one. That seed is Christ the head, and all in Christ. See 1Co 12:12 The whole spiritual seed of Abraham concentrates in Christ. The promise is to Christ and all in Christ. Paul understood Greek as well as his critics, and also knew what he meant.
3:16 Now the promises were made to Abraham and his seed - Several promises were made to Abraham; but the chief of all, and which was several times repeated, was that of the blessing through Christ. He - That is, God. Saith not, And to seeds, as of many - As if the promise were made to several kinds of seed. But as of one - That is, one kind of seed, one posterity, one kind of sons. And to all these the blessing belonged by promise. Which is Christ - including all that believe in him. Gen 22:18.
3:15-18 The covenant God made with Abraham, was not done away by the giving the law to Moses. The covenant was made with Abraham and his Seed. It is still in force; Christ abideth for ever in his person, and his spiritual seed, who are his by faith. By this we learn the difference between the promises of the law and those of the gospel. The promises of the law are made to the person of every man; the promises of the gospel are first made to Christ, then by him to those who are by faith ingrafted into Christ. Rightly to divide the word of truth, a great difference must be put between the promise and the law, as to the inward affections, and the whole practice of life. When the promise is mingled with the law, it is made nothing but the law. Let Christ be always before our eyes, as a sure argument for the defence of faith, against dependence on human righteousness.