But as many as received Him, to them He gave the right to become children of God, even to those who believe in His name, who were born not of blood, nor of the will of the flesh, nor of the will of man, but of God." John 1:9-13 (NAS)

This is a beautiful passage which us people from different nations are able to claim we are children of God.

The chosen people of God (Descendents of Abraham) believed that they are the children of God as through Abraham and all blessings of God are to them alone for quite some time.

We even see that Jesus healing a woman (click here- An excellent article, read it) who is not a descendant of Abraham but gets healing from Jesus based on her faith. (‘even dogs get what falls from the plates of the master') Also we see in bible that the word of god/salvation was taken to gentiles other than the descendants of Abraham only after the vision Peter received in Acts.

But as in John 3:16 "whosoever believes in him" no matter what caste, color, creed or religion its everyone in this world. The same applies in this word where we have this wonderful promise in this verse that whoever believes/receives/ accepts Christ into their hearts, they get the rights to become children of God. We have the right to call him 'Abba Father' Amen.

Some commentaries on this topic can be seen here