The Way of Perfection, by Teresa of Avila (1515-1582)
Explains the meaning of mental prayer.
O miserable world! Give hearty praise to God, daughters, that you have left so wretched a place, where people are honoured, not for their own selves, but for what they get from their tenants and vassals: if these fail them, they have no honour left. It is a curious thing, and when you go out to recreation together you should laugh about it, for it is a good way of spending your time to reflect how blindly people in the world spend theirs.
- Chapter 22
(Keep in mind that she is writing to sisters in a cloistered contemplative order.)