"Even a man who is pure in heart and says his prayers each night"

This is a line which appears repeatedly in the 1941 movie The Wolfman. The full poem is "Even a man who is pure in heart/and says his prayers by night/may become a wolf when the wolfbane blooms/and the autumn moon is bright," meaning in the movie that any man might become a werewolf, and meaning in a general sense that a man's baser instincts may take control no matter how good he appears to be. This is the scene Dr. Destiny is playing out on this page.