"God's concern to include all the ethnic peoples of the world in his saving purposes--in his final, eternal family--is unbreakably linked with the two greatest realities in the universe: God's very being as one God and the way God has ordained to put sinners in the right with himself through justification in Christ. Ethnic diversity is not connected to God marginally. It's connected at the center--his infinite being and his single, glorious way of justifying sinners.
As this sinks into our minds and hearts, the effect it should have is to change the way we think and feel about the racial and ethnic diversity in the world and the church. We are constantly in danger of feeling (even when we are not thinking this way) that God is partial to our tribe--that he has a special liking for our ethnicity and cultural norms.
This danger is especially present and unseen among majority cultures and majority ethnic groups...This makes us very vulnerable to the assumption that God is our God in away that minimizes his being the God of other ethnic groups.
May the astonishing way that Paul speaks in Romans 3:29-30 of justification by faith alone awaken us from this deadly assumption. And may it fill us with a sense of amazement at God's passion in the pursuit of all the ethnic groups of the world. May we never forget that his pursuit is rooted in God's being one infinite God and in his justifying sinners in one glorious way through faith alone in the blood and righteousness of his Son, Jesus Christ."
Bloodlines, pp. 154-155.