Gregory the Dialogist

Others as wild asses in the desert go forth to their work. Watching for a prey, they provide bread for their children. For the 'onager' is a wild ass; and in this place Heretics are rightly likened to 'wild asses,' in that being let loose in their pleasures, they are strange to the fetters of faith and reason. Hence it is written; A wild ass used to the wilderness that snuffeth up the wind of his love at his pleasure. …

Morals on the Book of Job, Book XVI ↗

Thomas Aquinas

However, there are some who do not harm others fraudulently like those already described, but through open violence. These men rush to do evil like people who are not restrained by the discipline of the law. He says about these men, "Others like the wild asses in the desert," the wild asses of the forests who are not domesticated to the service of men, "go forth to their work," to robbery like one who is enthusiastic for his profession. …

Commentary on Job ↗