^28-30 Now we, my brothers, are like Isaac, for we are children born “by promise”. But just as in those far-off days the natural son persecuted the “spiritual” son, so it is today. Yet what is the scriptural instruction? ‘Cast out the bondwoman and her son, for the son of the bondwoman shall not be heir with the son of the freewoman.’

³¹ So then, my brothers, we are not to look upon ourselves as the sons of the slave woman but of the free, not sons of slavery under the Law but sons of freedom under grace.