Romans 8:14 - Coke's Commentary on the Holy Bible

They are the sons of God— Isaac, by his super-natural birth, being in a peculiar manner the son of God,the Israelites his children were called by God himself his son, Exodus 4:22. But they were God's son only in an inferior sense: for by that relation they were entitled to nothing but the earthly inheritance. Whereas believers are in a higher sense the sons of God. Being spiritually begotten of God, they partake of his nature, are heirs of the heavenly country, and, if faithful unto death, by the redemption of their body may become immortal like God—they are capable of enjoying the everlasting inheritance. Perhaps also the high title of the sons of God is given to believers, to convey an affecting idea of their dignity and felicity; because, of all the things in which worldly men glory, noble birth is the chief.