i see a lot of this kind of idea tossed about, and was in fact earlier questioned about it in another thread.
people saying absolutely everyone is one of God's children.
here are a few verses speaking to the fact not all are God's children, but only those who are in covenant through Christ.
please add your own.
He came to His own, and those who were His own did not receive Him. 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. (Jn 1:11-14)
For you are all sons of God through faith in Christ Jesus. (Gal 3:26)
(...)just as He chose us in Him before the foundation of the world, that we would be holy and blameless before Him. In love He predestined us to adoption as sons through Jesus Christ to Himself, according to the kind intention of His will, to the praise of the glory of His grace, which He freely bestowed on us in the Beloved. (Eph 1:4-6)