There is a strange bookcase at the end of a chapel's corridor that is pitch black, save for a few lanterns lighting the way. As you approach the bookcase, you notice six conspicuous books with unique colors. These unique colors being: red, purple, white, gold, blue, and green. A note is laying in front of the books, telling you of a secret passage that activates when you pull one of the books. The note also reads "The location is in the titles". The six books have the following titles.
The Church's Hidden Archives
Purifying in The Tub
Bat out of Hell
Vowels with Noah: AEIOU
God's Word is True
The Devil's Tempting Lies
Which book do you pull to find the passage and why?
Hint 1
Upon closer inspection, the note seems to emphasize that the middle four titles are more important