“Abraham believed God, and God counted him as righteous because of his faith. The real children of Abraham, then, are those who put their faith in God.” Galatians 3:6,7 NLT.
The Jews of Paul’s day, and of Jesus’ day before him, took great pride in their status of “children of Abraham.” But Jesus boldly denied their claim; He told them that their hatred of Him showed clearly that they were not Abraham’s children.
As Paul was writing his letter to the believers in Galatia, their faith was under attack from Jews, attempting to convince them that they must now keep the whole Law of Moses in order to be saved. Paul, horrified by the spread of this heresy, wrote his letter to both take them to task for their submission to the false doctrine, and to instruct them in the true doctrine of salvation by faith in Jesus Christ alone.
Abraham’s righteousness, as declared by none other than God Himself, was a result of His believing in God. And thus, Paul says, his children are those who put their faith in God. The Jews, descended from Abraham, can be his true children by putting their faith in God; or they can reject the privilege of being his children by rejecting Jesus Christ and by putting their faith in their own works. And those of us who are not physically descended from Abraham can yet be his children when we put our faith in God, and in Jesus Christ Whom He has sent.
Abraham believed God, and God counted him righteous by faith. When we believe God, and put our faith in Jesus Christ, we are counted righteous by God, and are welcomed as true children of Abraham, children of faith, faith which pleases God.