Lo, the wolf hath seized a sheep by the throat, the devil hath enticed a man into adultery. The sinner must be excommunicated. But if he is excommunicated, he will be an enemy, he will plot, he will do as much harm as he can. Wherefore thou art silent, thou dost not censure, thou hast seen the wolf coming, and fled. Thy body has stood, thy mind has fled. For as joy is relaxation, sorrow contraction, desire a reaching forward of the mind; so fear is the flight of the mind.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).
Also cites: Tr. xlvi. 8