Denominationalism can be a tricky topic. For some people it is a contest, who is best? For others it is a proof, if God existed wouldn’t He cause His people to agree on everything? For other people it is simply a point of confusion, why can’t we all just get along?
I believe these questions all miss the point. They take the realities of human nature and pretend it should fit their preferences. In my examples the preferences expressed in the question were competition, anarchy and homogeneity. But none of these reflect the nature of all of humanity at any moment.
I think of denominations rather simply. It is a group of churches of like faith and order that choose to cooperate together for the purpose of missions or other mutual causes. Denominations can be large or small. They can be governed any number of ways. And they can be good or bad.
A number of things can make a denomination bad. I believe if it has a single autocratic leader, its already bad. If you don’t understand why, just wait until the day you have a bad person in the position. Bad doctrine will certainly make a denomination bad. Lead people astray and you will pay a high price. Bad organization will make a bad denomination. Good intentions require good structure and great follow through. I am sure the list could go on.
But in regards to all these different denominations, let me make a few observations. If you think they are all fighting with one another, get over it. Yes, you can find people who are that way. You can even find entire denominations that are that way. But an honest accounting would come to the conclusion they are few. And except on those larger issues, you will find they are mostly limited to young or young at heart believers.
What about those larger issues though. Honestly, some issues are worth confronting. Not by fisticuffs, not by shouting matches, but by reasonable conversation. Remember I said bad doctrine could lead people astray? If astray means sending them to hell we really should try to intervene within appropriate limits. (Yes, I am saying not everyone who calls themselves a Christian will be recognized as such by God.) This world acts as if addressing their spiritual falsehoods is the greatest rudeness. I would think letting people walk into eternal hellfire without a word of warning was much ruder.
This by the way is the answer to the other objections. God allows us our differences of opinions. Removing them would be equivalent to removing our freedom, and therefore our humanity. He makes Himself available by the Word and Holy Spirit, by nature and prayer. So Christians seek Him and they don’t all have the same personalities, preferences or experiences. So even with the same revelations, they come to different conclusions. God is willing to live with that, so we should be too.
For believers this means they have a point of responsibility. When one believes Jesus is God’s Son and the Second Person of the Trinity you would rather fellowship with others who believe and teach the same. The same truth applies to a bunch of other doctrinal points. At some level you begin to say a doctrine is minor enough that it is not an essential test of fellowship. But to decide that no point of doctrine is important enough to break fellowship, is equivalent to saying you will not stand up for God in any way.