“But to all who did receive him, who believed in his name, he gave the right to become children of God, who were born, not of blood nor of the will of the flesh nor of the will of man, but of God” (John 1:12, 13 ESV).
I thank God that no one is prohibited from the Kingdom of God because he doesn’t have the right bloodline. Indeed, all through Scripture, family relations are established (as in marriage), not on blood, but on Covenant. So it is with the Family of God. Those who are God’s true children are only His children by right of Divine adoption.