Galatians 4:28-30

4:28 But you, brothers and sisters, are children of the promise like Isaac. 4:29 But just as at that time the one born by natural descent persecuted the one born according to the Spirit, so it is now. 4:30 But what does the scripture say? “Throw out the slave woman and her son, for the son of the slave woman will not share the inheritance with the son” of the free woman.