27 For it is written:‘Be glad, barren woman,you who never bore a child;break forth and cry aloud,you who were never in labour;because more are the children of the desolate womanthan of her who has a husband.’
28 Now you, brothers and sisters, like Isaac, are children of promise.
29 At that time the son born according to the flesh persecuted the son born by the power of the Spirit. It is the same now.
30 But what does Scripture say? ‘Get rid of the slave woman and her son, for the slave woman’s son will never share in the inheritance with the free woman’s son.’
31 Therefore, brothers and sisters, we are not children of the slave woman, but of the free woman.