“The angel’s girdling”

“THOMAS himself told the story to his friend Reginald during the last period of his life. After he had been imprisoned, at the age of nineteen or twenty, his brothers sent a bejeweled courtesan to visit Thomas in his cell, to lure him from his resolve to become a mendicant friar. After he had rather roughly shown this damsel the door, Thomas fell into a deep, exhausted sleep, from which he awakened with a cry. He had cried out because in his dream an angel had girdled him in an extremely painful manner, in order to make him henceforth invulnerable to all temptations toward impurity. Whatever interpretation we may put upon this story, it is certain that Thomas—like Goethe, incidentally—always maintained that purity was a necessary condition for recognizing truth, for seeing reality. More than that, he fulfilled this condition in his own person. He was, it appears, a person of such unusual “simplicity,” and this “singleness of eye” gives him such “light,” that we are no doubt justified in speaking of charisma.” 

~Josef Pieper: Guide to Thomas Aquinas, Chap. X.

The Temptation of St. Thomas Aquinas, by Diego Rodriguez de Silva y Velázquez. 

Oil on canvas, 1632; Cathedral Museum of Sacred Art, Orihuela.