In The Way of Perfection, St. Teresa writes about the virtues of humility and detachment saying that, "They are two inseparable sisters."
Our saint warns that souls need to not feel secure or fall asleep. She advises souls to be alert in "going against our own will". Going against our own will is humility. She points out that turning and being against ourselves is a difficult thing because. . . we love ourselves greatly. How true this is!
One important way to practice detachment is to detach from the love of our bodies which demand so much comfort and strive to be more faithful to our duties. Our bodies want so much comfort that the more we give it the more it demands.
St. Teresa suggests that souls try to remember that everything is vanity and will all come to an end. It is a great help for souls to remove any attachment it might have to trivial things and to center its thoughts on eternal things.
The soul should embrace these two virtues and by doing so, imitate Christ who "was never for a moment seen without them!" Another interesting thing about these virtues is that they "have the characteristic of so hiding themselves from the person who possess them that these persons never see them or manage to believe that they even have them".