It is often stated that Christianity is divisive; not only divisive to the secular public and other religions, but to its own body. To some extent, this is true. However, those who raise this objection fail to see the obvious. Though there are many divisions, variants, or “brands” of Christianity; there is a common denominator that unites us all. The common denominator is the basics doctrines (or Mere Christianity) that all Christians share.
The objection is immaterial. Unity does not have to be uniformity. No matter what position is held in any area of knowledge, there will always be disagreement. I know of no one who has ever found another person in which they completely agreed on every idea, issue, or matter there ever was 100%; all one needs to do is ask any married couple. Because we are rational, independent free moral agents, we will always have our own views. Besides, if everyone completely agreed on everything, there would be no need for discussion—or any interaction for that matter.
Given the inevitability of disagreement, the manner in which differences are articulated is the key issue. I can discuss controversial issues with someone from any denomination courteously and respectfully. Though we may disagree on peripheral issues (that are not basic doctrines), we are still joined in Christ. I think that what matters the most is how we disagree, not that we disagree.
Division can have its benefits. Any time there is disagreement it creates the ability to dividing truth from error. If everyone was in conformity in all issues, there would be no motivation to examine our own thought and ideas—to test knowledge.
Division can also have dangers. On many occasions, people can become hostile to one another; peripheral issues become main issues and cause antagonistic divergence rather than respectful divergence. In addition, the complete ability and autonomy of the mind allows for foolish and mistaken beliefs, which develop cults and additional heresies.
Do best sum things up a church father once said:
In the Essentials—Unity; In the Non-Essentials—Liberty; In all things—Charity