Ephesians 1:
In love 5 he predestined us for adoption to sonship through Jesus Christ, in accordance with his pleasure and will — 6 to the praise of his glorious grace, which he has freely given us in the One he loves.
I sometimes wonder if the whole fascination with the notion of birth parents which is so common today is not on some level a rejection of the integral position adoption plays in Christianity.
If we do not take on the nature of our adoptive Father, our adoption is useless.
In the ancient world, adoption was final, you became the offspring of your parents, not a half and half almost non person (culturally speaking) like many would seem to have it today.
Likewise, people giving their children up for adoption seem to really want someone else to be responsible for raising their children, but have rights and privileges otherwise intact - this is not true adoption, no matter what the social services people seem to think.
I see the onus placed on adoption as a rationalization of abortion, and mentality that goes with it. “If i keep the child, then he grows up without a father, but since he is really mine alone, I will give him all the love he needs. No one else can give him the same love. Besides. If I know he is out there, I will worry that he is not being taken care of. Better that he die than suffer, and more important, that I not suffer.