So much so that even a couple of extremists who have obviously spent years studying his 'word' not be able to agree on what they're supposed to believe?
You may well have studied European and/or Church history, so forgive me for the simplified example Im about to give - I do so because it's very difficult to explain in a few sentences if you have no background in the topic.
What's going on here can be likened in a way to:
Imagine your great great grandfather was a carpenter. His son wrote down what his father said and did, but also commented in the writing that not everything his father said and did was recorded, but the son, your great grandfather, was fully aware of all these things, both written and unwritten but practiced.
Now, time marches on and your great grandfather builds his trade based entirely on what his father did and said, and everyone knows its both thats involved in the business, because they have the authentic word of the son.
Now, he has a son, your grandfather, and the business carries on booming, everyone adhering to what the founder, your great great grandfather, said and did, because they have both the written word, and the tradition handed down.
Your father carries on in exactly the same manner, and now, so do you.
BUT, another business sets up across the road, doing what you do, and cashing in on your great great grandfathers fame, only now, they are telling everyone certain things have to change, because even though your great great grandfathers instruction manual says to do x, they say he actually meant do xy.
Not only that, but they are also telling your workers that your great great grandfather never said abc, because its not written down!!!
So they grow their business and attract a lot of custom because its much easier to do xy than x, and they can skip abc completely because if your great great grandfather never wrote it down, then he never meant for abc to happen.
Even though you have 5 continuous generations of information, practice, tradition and the manual.
Who do you think would be more faithful to your great great grandfathers way of working - you and your workers, with your 5 generations of unbroken succession, or the bodget and leggitt cowboys who set up across the road, proclaim to know what your great great grandfather really meant, and offer their customers a completely adulterated version of your great great grandfathers manual.
That's what's going on with DCE. He's professing he knows more than the martyrs, doctors, fathers and saints of the church with 2000 years of unbroken theology doctrine faith and practice.
Because he reads the Bible and takes what he wants from it according to his own personal interpretation.