The New Testament uses the word adopted many times but it's a mistranslation. Either you are adopted into the family of God or Born Into the family of God and there are more references to being born of God, Born Again, born of the spirit, born from above, born of incorruptible seed than anything else. It cannot be both meaning it's one or the other. In order to become a new creation in Christ you must be born into the family of God and not adopted. Even in natural adoptions you still retain the nature of your original natural father but once we are in Christ we've been given a brand new nature which is the very same nature that Jesus was born with and no longer have the adamic nature, and this is impossible through adoption.