Born in the Castilian town of Avila in 1515, Teresa entered the Carmelite convent of the Incarnation when she was twenty-one. Tormented by illness, doubts and self-recrimination, she gradually came to recognize the power of prayer and contemplation—her spiritual enlightenment was intensified by many visions and mystical experiences, including the piercing of her heart by a spear of divine love. She went on to found seventeen Carmelite monasteries throughout Spain. Teresa always denied her own saintliness, however, saying in a letter: "There is no suggestion of that nonsense about my supposed sanctity." This frank account is one of the great stories of a religious life and a literary masterpiece—after Don Quixote, it is Spain's most widely read prose classic.

For more than seventy years, Penguin has been the leading publisher of classic literature in the English-speaking world. With more than 1,700 titles, Penguin Classics represents a global bookshelf of the best works throughout history and across genres and disciplines. Readers trust the series to provide authoritative texts enhanced by introductions and notes by distinguished scholars and contemporary authors, as well as up-to-date translations by award-winning translators.