Do not fear what you are about to suffer. Behold, the devil is about to cast some of you into prison, that you may be tested, and you will have tribulation ten days. Be faithful until death, and I will give you the crown of life. Revelation 2:10 (NASB) - Jesus Christ to the church at Smyrna
What if you received a letter from the Lord that said the same thing? Uh, things will pretty much suck for ten days, then you will die. But don't fear.
What would you do? Write your will? Eat as much of your favorite food as possible before it starts? Me? I'm sure that I wouldn't be perfectly calm, but if I knew this was directly from God, I could see how one could take this with an increase in faith. Here's where the rubber meets the road of faith.
I think many things in life are analogous to this. You learn or train for something, then you face it with much anticipation. Yet, when we are immersed in it and past the point of no return, we are quite able to handle the situation. Even when we face death.