Children and Heirs
26 For ye are all the children of God by faith in Christ Jesus. 27 For as many of you as have been baptized into Christ have put on Christ. 28 There is neither Jew nor Greek, there is neither bond nor free, there is neither male nor female: for ye are all one in Christ Jesus. 29 And if ye be Christ’s, then are ye Abraham’s seed, and heirs according to the promise.
Under grace the believer is no longer under the surveillance of the schoolmaster, the guardianship of law. Rather the believer is now a full grown son. Instead of the believer being under the control the law and because of his vital union with Christ — that union being the product of his faith in Christ — is now a child of God. Whether Jew or Gentile, bond or free, male or female. All believers have the same status as children of God.
Baptized into Christ, baptizo – defined to put or place into — the Holy Spirit places the believing sinner into vital union with Christ. This is not water baptism.
In verse 29, Paul contrast with the Judaizers who taught that being placed under the Law made one the progeny of Abraham and thus receive favor from God. Paul shows that faith in Christ, the promised seed of Abraham, makes Abraham the spiritual father of all believers.