No one questions that Scripture teaches unity for the Church and humanity at large. It is the intention of creation. It finds fulfillment in the end when Jesus unites all things under his authority.
What is interesting though are the stories that show God dividing the people. The word of God divides (Heb. 4:12). Jesus brought a sword that would divide (Matt. 10:34-36). One story in the Old Testament is particularly striking: the story of the Tower of Babel.
The story begins in Genesis 11. The first verse says, “Now the entire earth was of one language and common words.” 
This brings to mind exhortations of Paul who says, “Now I beseech you, brethren, by the name of our Lord Jesus Christ, that ye all speak the same thing, and that there be no divisions among you; but that ye be perfectly joined together in the same mind and in the same judgment.”
The people came together, united, to build themselves a city and a tower. They were united in purpose, had the same mind, the same judgment. This unity of mind and purpose seems to align with the unity that is taught throughout scripture. Why, then, did God divide these ancient people?
Leithart says, “Division and false union come together in the tower of Babel episode, the great biblical story of false unification and final dispersal.” The intentions of the builders of the tower were judged by God as being anti-unity. What were the builders doing that made God disperse them and break their unity?
 Old Testament quotations comes from John Goldingay’s translation of the Old Testament called “The First Testament”
 1 Cor. 1:10 KJV
 Peter J. Leithart: The End Of Protestantism: Pursuing Unity in a Fragmented Church