There is a little book that every Catholic (or ex-Catholic) of a certain age will know: The Imitation of Christ by Thomas a Kempis. Perhaps no other book, not even the Bible, has for so long been a staple of Catholic spirituality. I first encountered Thomas in my early teens, at the urging of one of my teachers, but I was too busy then discovering girls to have any use for sanctity. I read the book again as I went through a period of religious fervor as a college student, and this time something of what Thomas was saying resonated with my own spiritual inclinations.
Of course, Thomas' exhortations are couched in the theological language of the 15th century, and the book is Christ-centered in an entirely orthodox way. But the gist of the author's message could be embodied within any spiritual system, East or West, secular or religious. Know yourself, he says. As far as possible, stay free of worldly entanglements. Value solitude and silence. Cultivate simplicity. Love others. And, of course: "All perfection in this life is accompanied by a measure of imperfection, and all our knowledge contains an element of obscurity."
Scientific learning is not to be despised, says Thomas, but a pure conscience and a holy life is much to be preferred. For some years, in my late teens and early twenties, I pursued both. I did very well with the study of science, not so well with the pure conscience and holy life. By my mid-twenties, the whole creaking apparatus of Catholic orthodoxy had begun to fall away, and with it the vain self-abnegation and hollow supernaturalism of The Imitation of Christ. Thomas advised loving the Creator, not the creation; I had become increasingly enamored of the natural world. Not, I hasten to add, as a distraction from the spiritual ideals of Thomas a Kempis, but rather as the source of the very things he urged upon us: self-knowledge, solitude, silence, simplicity and love. I was now reading Thoreau with the same attention I had formerly given Thomas; the two teachers, one secular, one religious, were in some ways not so far apart.