Some thoughts from Dr. Russell Moore on transracial adoption:
As believers in Jesus Christ, we were inter-racially adopted. The Scripture spends a lot of time saying that we were part of the nations, we were those who were, as Paul says to the church at Ephesus, cut off from the promises of God. We were far away but God has brought us near in Christ Jesus. He has given us a new household, and new family with new brothers and new sisters. We are part now of a new tribe, of a new family.
What's happening as we adopt two Ethiopian children is a picture of that. If we were to prize our flesh, our bloodline, our family heritage above the love and transcendence that comes through adoption, we'd really be following the way of the flesh and not way of the spirit, and we'd be cutting ourselves off from the very promises that saved us.
We want our children to know from the beginning that they are a welcome and received part of our family. They are not strangers, and not just orphans with a better home. They are part of our family. There will be some differences, and some conversations that we'll need to have with them so they'll be prepared for the kinds of questions they will get. But what a great opportunity for us to be to training them in the nurture and admonition of the Lord! They will be able to say that they are Ethiopian and they are part of a "Jewish" family through the gospel of Jesus Christ. And if you follow Christ, you too are part of this big, global, household family from every tribe, every tongue, every nation and every language. The blood of Christ trumps the blood of our backgrounds.
Here's another great article Dr. Moore writes on Transracial Adoption, the Gospel, and You.