St. Teresa of Avila
The Way of Perfection
Chapter 10 · Part 2 of 2
Teaches that detachment from the things aforementioned is insufficient if we are not detached from our own selves and that this virtue and humility go together
Oh, God help me! That there should be complaining like this among nuns! May He forgive me for saying so, but I am afraid it has become quite a habit. I happened to observe this incident once myself: a nun began complaining about her headaches and she went on complaining to me for a long time. In the end I made enquiries and found she had no headache whatever, but was suffering from some pain or other elsewhere.
These are things which may sometimes happen and I put them down here so that you may guard against them; for if once the devil begins to frighten us about losing our health, we shall never get anywhere. The Lord give us light so that we may act rightly in everything! Amen.
Source: The Way of Perfection (CCEL)