I just finished reading a chapter called "Sons of God" in J. I. Packer's book Knowing God. I can't help but share some of what he wrote.
Packer defines a Christian like this: "A Christian is one who has God as Father." Meaning, not everyone on planet Earth is a child of God; only those who have been adopted into the family are children of the Most High. We aren't born into this family, we are adopted and this is a powerful reality.
In ancient times adoption was different than it is today. Adoption was usually done by rich people who didn't have children of their own. The wealthy man would adopt a young man who was worthy to carry on the family name and have the family inheritance. Adoption was not like it is today when little babies are adopted just for the purpose of being part of a loving family.
God's adoption is done in somewhat of a mixture of the ancient and modern ideas of adoption. God adopts us when we are not infants. God adopts us to make us heirs. He takes those whom He redeemed on the cross and makes them heirs. But God does not need to pass on His name or inheritance; rather, like modern adoption God does this purely out of love and free choice. When a family adopts a child today they do it simply out of the outpouring of their love; God does too.
We've been adopted. So what?
Adoption changes everything. No longer is Yahweh God's covenant name with us. Yahweh was God's covenant name with the nation of Israel (that we've been grafted into); it is a name that reflects His self-existent sovereignty. Yahweh is still a fantastic name that we can call God, but it is not the most representative of the new covenant He has made with us. Father is God's new covenant name. Father has been added to Yahweh because He promises to be our Father and treat us as His children.
Adoption is the highest prize of the Gospel. Justification is the primary prize but clearly adoption is higher. Justification yields forensic forgiveness but adoption adds familial love. Adoption ensures that we are loved like children without a doubt. Adoption means we that Jesus is our brother and everything that is promised to Him is also ours as co-heirs.
Everything about our Christian lives has to be understood in relation to our adoption according to Packer. For instance, why do we obey commands? Is it to earn salvation? Is it out of mortal fear? No. We obey commands because we want to please our Heavenly Father. Why can we trust God at the wheel of our life? We trust because we, like little children, believe our Dad is a good driver. You've never seen a 3-year-old backseat driver have you?
God shows love to us in adoption. God didn't conceive you and therefore was compelled to have you in His family. God chose to adopt you. This is love. We are sons and daughters of God. And get this: God loves us the same as He loves our brother Jesus.
There is so much hope, love and wonder in the subject of our adoption. I could go on, but you'd be better off reading J. I. Packer's book Knowing God.
I do want to leave you with one more bombshell truth. Adoption is the beginning of a relationship. Justification is once and for all, and hallelujah for that; but adoption is even better. No one adopts a child and then ignores him/her. Instead, they adopt the child and then love them forever from that point on. God the Father does the same thing. He adopts us and then proceeds to love us as His children forever!
If you are a Christian you are a child of the King. Thank God for His blessing of adoption today.