Coincidentally, I just finished reading a memoir by someone who was a nun for the Missions of Charity (Mother Teresa's group). She was a nun for 20 years before leaving. Very interesting. It is NOT a scathing denunciation of Mother Teresa although the book is not 100% positive either.
I would recommend it if you want to learn a bit about the "behind the scenes" of being a nun and a bit about Mother Teresa. The author had some access to her and definitely knew a lot about the running of the order.
I was impressed by this quote from the end of the book and actually wrote it down. She is speaking, in this quote, about her conversation with a priest who she knew from when she was a nun and then met up with at a conference after she left the order.
I particularly like the concept of "god" being the best part of you (rather than external). I don't believe in god, of course, but I do think that any spirituality that we have as human beings comes from within us (our brains) and that is the only rational way to think about it.
Here's the quote:
“…I don’t have the courage to tell him about the afternoon near dusk when I sat on a hill overlooking a pond in Vermont. That day I called out to God, loudly. I yelled, “So are you out there? And if you are, what are you like? Tell me. I’ve got to know.” I don’t tell Father Bob about the still, small voice I heard within. Look inside yourself, the voice said. God is like the best parts of you.
From there it was a short step to God IS the best parts of you.
I don’t tell Father Bob how the stories about God no longer ring true, how physics and literature and music feel so much more honest than theology. I don’t tell him that I’ve learned to be content with mystery, that the universe and its secrets excite me. I don’t mention that living mindfully, trying to do good while avoiding harm, works better than keeping the Rules [of the religious order] ever did.”
--Mary Johnson, An Unquenchable Thirst: Following Mother Teresa in search of love, service, and an authentic life.