'Sons' in the Bible

So understand that it is the people who live by faith [with confidence in the power and goodness of God] who are [the true] sons of Abraham.

For you [who are born-again have been reborn from above—spiritually transformed, renewed, sanctified and] are all children of God [set apart for His purpose with full rights and privileges] through faith in Christ Jesus.

so that He might redeem and liberate those who were under the Law, that we [who believe] might be adopted as sons [as God’s children with all rights as fully grown members of a family].

And because you [really] are [His] sons, God has sent the Spirit of His Son into our hearts, crying out, “Abba! Father!”

For it is written that Abraham had two sons, one by the slave woman [Hagar] and one by the free woman [Sarah].