So........why?

I'll add to this as time goes on, no doubt, because there are a lot of reasons, a lot of thoughts about why, but I will never give you a better answer than this: To learn to always live in Christ.

As to scripture: faith consists in submitting; private interpretation consists in judging. In faith by hearing, the last word rests with the teacher; in private judgment it rests with the reader, who submits the dead text of Scripture to a kind of post-mortem examination and delivers a verdict without appeal: he believes in himself rather than in any higher authority. But such trust in one's own light is not faith.

Some will say their efforts to read, interpret, and understand scripture are prayerfully undertaken,and always guided by the Spirit. I have done so myself. IT seemed to me that I had EVERY right to assume so. Pretty arrogant, in hindsight, especially considering how little I actually knew then, let alone now. Now, amazingly, I would say that personal revelation should not be, as it has been, the impetus for denominational development or the creation of a "personal faith" because "I'm not into organized religion."

Even so, if these prayerful interpretations were always, entirely, and universally accurate, there would never be disagreement regarding what it says, what it means, how it is to be understood, nor would there be any division in the "church". Ha!

Tradition AND Scripture, whether we like it or not, is the truest expression of God's continued and unceasing will, and the ongoing work of the Holy Spirit on earth. How is that way of receiving the Truth any different from making it up as we go along and changing it to meet our requirements and design in our own comfort with it? Because it's been handed down for two thousand years, with consistency, mindful of and in obedience to the actual Deposit of Faith and not invented in support of protest or rebellion, convenience or greed. So, it's different alright, but as compared to what? Five? Fifty? Five Hundred years of protest and rebellion?

Or maybe, just now, when you thought of this great new scriptural concept when you picked a verse or two at random? Personal revelation is intended to help us ask questions, to deepen our understanding in our efforts to be more holy, more like Jesus, to facilitate our study, to grow, and to learn. Not to start new denominations out of disagreements and rebellions. It's hard to keep our egos in check and just follow God though, huh? I know!

Shall I quote the scriptures that define how these differences should have been handled at EVERY stage within the church, every time it happened or now, when it is happening, and point to the incorrect behaviors? I hate that. Don't make me. It makes me sound mean and cynical.

Romans 3:28
For we maintain that a man is justified by faith apart from works of the Law.
James 2:24-26
You see that a man is justified by works and not by faith alone. In the same way, was not Rahab the harlot also justified by works when she received the messengers and sent them out by another way? For just as the body without the spirit is dead, so also faith without works is dead.

If those look like a contradiction, then your mind is failing to grasp what your heart already knows.

So many examples in scripture defy every argument men have or ever will try to make against God's calling to them, in both the Old and the New Testament. It's simple really, people just don't want to have to actually bear the cross. We mostly don't, but God wants us to. We have and will go to extraordinary ends to reshape His intentions to our own liking, even though we deny ourselves His gifts in so doing. Silly people, God really is on our side.