One of my all time favorites is the Way of the Pilgrim, by the Pilgrim. Its out of character for me, with it being a book written about Orthodox prayer life, but its one of my favorites anyway. One thing that I'm thankful for is how the Pilgrim struggled with an old translation of the Bible, in church Slovanic and how he felt he was blessed more by God for putting the extra effort into studying a more faithful translation.
And yours would be?
And yours would be?