Gregory the Dialogist : Which conduct the Lord by the Prophet well reproves, under the character of Babylon, saying; "Thorns and nettles shall spring up in her houses, and the bramble in the fortresses thereof." For what do we understand by 'nettles,' but the irritations of thoughts, and what by 'thorns,' but the piercings of sins? Nettles therefore and thorns spring up in the houses of Babylon, because in the disorder of a reprobate mind there arise longings of thoughts which exasperate, and sinful deeds which wound. But they who act thus have others also more wicked than themselves as their defenders. Whence he there fitly subjoined immediately, "And the bramble in the fortresses thereof." For the bramble is crowded with such a circle of thorns, that it can hardly be touched from its roughness. The nettle and the thorn therefore spring up within, but both of them are fortified without by the bramble: because, namely, smaller offenders commit any kinds of evil, but greater and most abandoned ones defend them. — Morals on the Book of Job, Book 33