The idea some have is, speak with confidence and its a proud thing. Speak with a wavering mouth, and its somehow called humility.
Hmmmn, I didn't know then, back about 25 to 30 years ago, at 10th church listening to Dr. Boice that he was such a humble man. Every sermon he gave was framed this way: here's my opinion (and yes he would say opinion), and now, let's look at how Knox understood this. And thirdly we'll look at Zwingli's interpretation of it. And then, after laying out three possibilities, he would say, now I think this is the best of the three. But he would state it as only a possibility.
Perhaps he did teach with humility, but he also taught with meagerness of bread. Back then, to this day, I can't recall one message he gave or one thing I learned from it.
On the other hand, when I heard Mr. Camping say, "This is what the Bible teaches"--on marriage divorce, qualifications for elders, speaking in tongues, the Sunday Sabbath, on without a parable He did not speak, first, on the apostasy of the churches, followed by the end of the Church Age, etc, etc. etc. I learned a tremendous amount of information about the Bible. I learned truth. And I heard the voice of Christ spoken (i.e. Truth) spoken through that ministry and that man.
No, when it comes to the Bible true humility is NOT saying I think so, or maybe this or maybe that---that very well may be false humility (pride) and the lifting up of man's voice (doubt) over and above the voice of Christ (truth spoken with authority as comparing Scripture with Scripture confirms it).