Need help with Libri Prohibiti and Avicenna - Sufficientia book

I have a problem with the side quest where i need to get the forbidden book. You see the problem is I took the book already before now its marked as a quest item. I can’t drop it or put it anywhere so now when i have to strip down to join the monastery it goes in the chest! So now im confused and stuck? What can I do? I tried leaving by sneaking out and getting it and henry goes ooh this is the book (game saves) i sneak back in. Few mins later in the day one of the monks yells at me then kicks me out saying I left so I broke the worse rules. Now what can I do? Not do the quest or?