AUV(i)
25 Now this woman, Hagar, is similar to Mount Sinai, in Arabia, and represents the present [earthly] Jerusalem [i.e., Israel], consisting of children in bondage [to the law of Moses].
26 But the heavenly Jerusalem [Heb. 12:22] consists of free people, and is the mother of us [Christians].
27 For it is written [Isa. 40:1], “[Woman] you should be happy that you have not had children. Cry over your inability to experience the pain of childbirth. For the deserted woman has had more children than the one with a husband.”
28 Now, brothers, you [Christians] are children of the promise [made to Abraham. See 3:29] just like Isaac, [Abraham’s son] was.
29 But, just as it was then --- the son born in the ordinary way [i.e., Ishmael] persecuting the one born according to the Holy Spirit’s [leading, i.e., Isaac] --- so it is now [i.e., Jews urging compliance with the requirements of the law of Moses persecuting those who refuse to return to dependance on that law for salvation. See 3:1-3].
30 What does the Scripture say about this matter? [It says, Gen. 21:10-12], “Get rid of the slave woman [Hagar], with her son [Ishmael]; for the son of the slave woman [Ishmael] will not inherit [what God promised to Abraham and his descendants], along with the son of the free woman [i.e., Isaac].”
31 Therefore, brothers, we [Christians] are not the [spiritual] children of the slave woman [Hagar] but of the free woman [Sarah].