The Bible teaches that there is one human family, equally fallen in sin and equally in need of the same redemption in Jesus Christ. The gospel of Jesus Christ is equally for every nation, tribe, and tongue. Regardless of ethnic background or physical features, those who are in Christ are one family, one people, and indeed members of the same body. Likewise, those who are not in Christ are equally condemned regardless of bloodline or appearance. The Bible, therefore, leaves no place for racism whatsoever in the people of God.
When God makes his covenant with Abraham, He says to him:
"In you all the families of the earth will be blessed," (Genesis 12:3).
God later echoes this covenant:
"In you and in your seed shall all the families of the earth be blessed," (Genesis 28:14).
The Apostle Peter (Acts 3:25-26) and the Apostle Paul (Galatians 3:16) both demonstrate that the promised seed is Christ and that it is through Him that all the families of the world are blessed. All of them. The gospel is for every people, and that was God's professed plan from the beginning! This is why Paul also preaches:
"He made from one man every nation of mankind to live on all the face of the earth, having determined their appointed times and the boundaries of their habitation, that they would seek God, if perhaps they might grope for Him and find Him, though He is not far from each one of us," (Acts 17:26-27).
and a few lines later in the same sermon:
"God is now declaring to men that all people everywhere should repent, because He has fixed a day in which He will judge the world in righteousness through a Man whom He has appointed, having furnished proof to all men by raising Him from the dead,” (Acts 17:26-27).
"All people everywhere" clearly means all people of every nation and ethnicity everywhere. All men are called to repent and believe on Christ. In praise of Christ the scriptures say:
"You were slain, and purchased for God with Your blood men from every tribe and tongue and people and nation," (Revelation 5:9)
The glorious truth is that Christ purchased by his blood the redemption of people of every ethnic background and of every physical description. All who repent and believe were equally bought with the blood of Christ. What is more, Peter writes:
"you are a chosen race, a royal priesthood, a holy nation, a people for God’s own possession, so that you may proclaim the excellencies of Him who has called you out of darkness into His marvelous light; for you once were not a people, but now you are the people of God; you had not received mercy, but now you have received mercy," (1 Peter 9-10).
The gospel, therefore, turns members of every nation and people into one new nation and people, a new creation, a new humanity. Before we were in Christ, we may have been separate peoples, but now we are one: the people of God! Biblically, humanity is not divided into "races" of men defined by arbitrary physical characteristics. In fact, in the grand scheme of things, there are only two categories that matter: the old man and the new; those who are in Adam and those who are in Christ; the nations and peoples of this world who are called graciously to repentance, and the holy nation that is the people of God made up of all who have repented and believed on Jesus Christ.
It is sin and unbiblical error for a Christian to be racist within the Church because everyone who is in Christ is his brother. They are members of the same body regardless of skin tone or national origin. It is likewise sin and unbiblical error for a Christian to be racist toward those outside the church because Christ died for people of every ethnicity and every color, language, and body type. The Christian is sent to preach the gospel equally to all of them, (Matthew 28:19-20). Racism is therefore worldly, unbiblical, and has no place in the Christian life whatsoever.