Galatians 4:7

Galatians 4:7. So that thou art no longer a slave, but a son, etc. Inference from Galatians 4:5-6. The second person individualizes and Brings it home to each reader. ‘Son,' in opposition to ‘slave,' but not, of course, to the exclusion of daughter. For the Apostle had distinctly declared, Galatians 3:28, that the sexual, as well as other differences, disappear before Christ in the general religious equality. He had here in view probably not the Jewish, but the Roman law, which was most familiar to his readers and which gave daughters and sons, adopted as well as native children, a title to the inheritance; while the Jewish law excluded the daughters, except in default of male heirs (Numbers 27:1 ff.; Numbers 36:1 ff.), but required the first born son to support them till they were married.

And if a son, then an heir through God. This is the most approved reading, of which the received text: ‘of God through Christ,' is a correct explanation, in conformity with Romans 8:17. The word ‘God' is here used in the widest sense of the triune God, from whom we derive our sonship and heirship in opposition to the law and to carnal descent from Abraham. For the Father sends His only begotten Son, the Son delivers us from the slavery of the law and reconciles us to the Father, the Holy Spirit applies the sonship to our heart and bears witness to it.