In these verses the apostle illustrates the difference between believers who rested in Christ only and those judaizers who trusted in the law, by a comparison taken from the story of Isaac and Ishmael. This he introduces in such a manner as was proper to strike and impress their minds, and to convince them of their great weakness in departing from the truth, and suffering themselves to be deprived of the liberty of the gospel: Tell me, says he, you that desire to be under the law, do you not hear the law? He takes it for granted that they did hear the law, for among the Jews it was wont to be read in their public assemblies every sabbath day; and, since they were so very fond of being under it, he would have them duly to consider what is written therein (referring to what is recorded Gen. 16 and 21), for, if they would do this, they might soon see how little reason they had to trust in it. And here, 1. He sets before them the history itself (Gal 4:22, Gal 4:23): For it is written, Abraham had two sons, etc. Here he represents the different state and condition of these two sons of Abraham - that the one, Ishmael, was by a bond-maid, and the other, Isaac, by a free-woman; and that whereas the former was born after the flesh, or by the ordinary course of nature, the other was by promise, when in the course of nature there was no reason to expect that Sarah should have a son. 2. He acquaints them with the meaning and design of this history, or the use which he intended to make of it (Gal 4:24-27): These things, says he, are an allegory, wherein, besides the literal and historical sense of the words, the Spirit of God might design to signify something further to us, and that was, That these two, Agar and Sarah, are the two covenants, or were intended to typify and prefigure the two different dispensations of the covenant. The former, Agar, represented that which was given from mount Sinai, and which gendereth to bondage, which, though it was a dispensation of grace, yet, in comparison of the gospel state, was a dispensation of bondage, and became more so to the Jews, through their mistake of the design of it, and expecting to be justified by the works of it. For this Agar is mount Sinai in Arabia (mount Sinai was then called Agar by the Arabians), and it answereth to Jerusalem which now is, and is in bondage with her children; that is, it justly represents the present state of the Jews, who, continuing in their infidelity and adhering to that covenant, are still in bondage with their children. But the other, Sarah, was intended to prefigure Jerusalem which is above, or the state of Christians under the new and better dispensation of the covenant, which is free both from the curse of the moral and the bondage of the ceremonial law, and is the mother of us all - a state into which all, both Jews and Gentiles, are admitted, upon their believing in Christ. And to this greater freedom and enlargement of the church under the gospel dispensation, which was typified by Sarah the mother of the promised seed, the apostle refers that of the prophet, Isa 54:1, where it is written, Rejoice, thou barren that bearest not; break forth and cry, thou that travailest not; for the desolate hath many more children than she who hath a husband. 3. He applies the history thus explained to the present case (Gal 4:28); Now we, brethren, says he, as Isaac was, are the children of the promise. We Christians, who have accepted Christ, and rely upon him, and look for justification and salvation by him alone, as hereby we become the spiritual, though we are not the natural, seed of Abraham, so we are entitled to the promised inheritance and interested in the blessings of it. But lest these Christians should be stumbled at the opposition they might meet with from the Jews, who were so tenacious of their law as to be ready to persecute those who would not submit to it, he tells them that this was no more than what was pointed to in the type; for as then he that was born after the flesh persecuted him that was born after the Spirit, they must expect it would be so now. But, for their comfort in this case, he desires them to consider what the scripture saith (Gen 21:10), Cast out the bond-woman and her son, for the son of the bond-woman shall not be heir with the son of the free-woman. Though the judaizers should persecute and hate them, yet the issue would be that Judaism would sink, and wither, and perish; but true Christianity should flourish and last for ever. And then, as a general inference from the whole of the sum of what he had said, he concludes (Gal 4:31), So then, brethren, we are not children of the bond-woman, but of the free.

But as then he - Ishmael, who was born after the flesh - whose birth had nothing supernatural in it, but was according to the ordinary course of nature,

Persecuted him - Isaac, who was born after the Spirit - who had a supernatural birth, according to the promise, and through the efficacy, of the Holy Spirit, giving effect to that promise - Sarah shall have a son, Gen 17:16-21; Gen 21:1, etc.

Persecuted him; the persecution here referred to is that mentioned Gen 21:9. It consisted in mocking his brother Isaac.

Even so it is now - So the Jews, in every place, persecute the Christians; and show thereby that they are rather of the posterity of Hagar than of Sarah.

Nevertheless, what saith the Scripture?.... This is a Talmudic form of citing Scriptures, and answers to , "what says the Scriptures (e)?" the passage referred to is Gen 21:10 and which are the words of Sarah to Abraham; but inasmuch as she spake them under divine inspiration, and they were approved of and confirmed by God, as appears from Gen 21:12 they are ascribed to God speaking in the Scripture:

cast out the bondwoman and her son, for the son of the bondwoman shall not be heir with the son of the free woman. There is very little difference in the citation from the original. The apostle omits the word "this" in both clauses, which though very proper to be expressed by Sarah, to point out the person she meant, and as being in a vehement passion, was not absolutely necessary to be retained by the apostle, since by the context there is no difficulty of knowing who is meant by her; though the Alexandrian copy has the word in it: and instead of "with my son, with Isaac", the apostle says, "with the son of the free woman, Sarah"; there speaking of herself, whose character the apostle gives, in opposition to the bondwoman: in like manner a Jewish writer (f) reads and interprets it,

"for the son of this woman shall not be heir , "with the son of the mistress".''

The casting of Hagar and Ishmael out of Abraham's family was a type and emblem of the rejection of the carnal and self-righteous Jews from the Gospel church state; nor ought any carnal persons, any that are after the flesh, unregenerate ones, or that trust to their own righteousness, to be in a Gospel church; as they will also be excluded and thrust out of the kingdom of heaven, into which no unregenerate and unrighteous, or self-righteous persons shall enter. The Jews make this ejection of Hagar and her son to be both out of this world and that which is to come (g). The reason given why the one should not be heir with the other perfectly agrees with the Jewish canons; which was not because he was the son of a concubine, for the sons of concubines might inherit, if they were Israelites, and free, but because he was the son of a bondwoman, for thus they run (h);

"all that are near of kin, though by iniquity, are heirs, as they that are legitimate; how? thus for instance, if a man has a son that is spurious, or a brother that is spurious, lo, these are as the other sons, and the other brethren for inheritance; but if, , "his son is by an handmaid", or by a strange woman, he is no son in any of these matters, , "and no heir at all":''

and again (i),

"an Israelite that hath a son by an handmaid, or by a Gentile, seeing he is not called his son, he that he has after him by an Israelitish woman, , "is the firstborn for inheritance", and takes the double portion.''

The reason assigned for non-inheritance in the text implies that the children of the free woman, the spiritual seed of Abraham, shall inherit the privileges of God's house, the blessings of grace, and eternal glory; they are children of the promise, and heirs according to it; when the children of the bondwoman, self-righteous ones, shall not; for the inheritance is not of the law, neither are they heirs who are of the works of it; nor is it to be enjoyed by mixing the law and Gospel, grace and works, in the business of salvation.

(e) T. Bab. Beracot, fol. 9. 2. (f) R. Abraham Seba, Tzeror, fol. 21. 3. (g) Pirke Eliezer, c. 30. (h) Maimon. Hilch. Nechalot, c. 1. sect. 7. (i) Ib c. 2. sect. 12.

persecuted--Ishmael "mocked" Isaac, which contained in it the germ and spirit of persecution (Gen 21:9). His mocking was probably directed against Isaac's piety and faith in God's promises. Being the older by natural birth, he haughtily prided himself above him that was born by promise: as Cain hated Abel's piety.

him . . . born after the Spirit--The language, though referring primarily to Isaac, born in a spiritual way (namely, by the promise or word of God, rendered by His Spirit efficient out of the course of nature, in making Sarah fruitful in old age), is so framed as especially to refer to believers justified by Gospel grace through faith, as opposed to carnal men, Judaizers, and legalists.

even so it is now-- (Gal 5:11; Gal 6:12, Gal 6:17; Act 9:29; Act 13:45, Act 13:49-50; Act 14:1-2, Act 14:19; Act 17:5, Act 17:13; Act 18:5-6). The Jews persecuted Paul, not for preaching Christianity in opposition to heathenism, but for preaching it as distinct from Judaism. Except in the two cases of Philippi and Ephesus (where the persons beginning the assault were pecuniarily interested in his expulsion), he was nowhere set upon by the Gentiles, unless they were first stirred up by the Jews. The coincidence between Paul's Epistles and Luke's history (the Acts) in this respect, is plainly undesigned, and so a proof of genuineness (see PALEY, HorÃ&brvbr PaulinÃ&brvbr).