Have you ever "intentionally" not prepared yourself? Luke 21-22

I spend my time making presentations on a variety of subjects.   Although I often don't know the exact words I am going to say before I make those presentations, I know the thoughts in my head that I have prepared ahead of time.  I typically know my outline.  I typically know my persuasive language.  I typically know, most of the time, one or two illustrations I am going to use.   I have been taught to be prepared to know what I am to say.  Every speech class I have ever taken told me to "prepare" the speech in this way or that way.   We grade our students on their preparation in speech class as much as delivery.   Politicians use tella-promters to make sure the "exact" words are being stated.    So, when I read the following verse about the end times and how believers will be treated and what they should do, I stand somewhat amazed and recoil just a bit:

Luke 21:14,15 - So make up your minds not to prepare beforehand to defend yourselves; for I will give you utterance and wisdom which none of your opponents will be able to resist or refute.

When God's Word tells us that the "just shall 'LIVE' by faith," this is exactly what that means.  Yes, we are saved by faith, but when it comes to living after our salvation nothing changes.   Jesus tells His disciples to "SET YOUR MINDS NOT TO PREPARE" before you have to defend yourself because, when the time comes, He will fill our minds and hearts with the proper words.   Think about that in our society.  I recently had to be a witness in a death case.   The lawyer prepared me on what he would ask and what the other attorney would ask.   They were over prepared.   I have, at times, gone into meetings to make a presentation without knowing what I was supposed to be talking about.   But, even then, I had some preparation in that I relied upon my own knowledge.  Here, Jesus is telling us that to live by faith for Him is to cast yourself into His care and allow Him to defend you by allowing Him to give you the exact words you will need.   This is an extreme act of faith.   This is "living by faith."   This is why we read God's Word.  God's Word strengthens our faith.   We need more faith - not more preparation for defense.  I wonder if we read God's Word more and memorized it if that would add to what God will give us to say when we need it?