Gregory the Dialogist

Thou shalt be hid from the scourge of the tongue. Neither shalt thou be afraid of calamity when it cometh. 'The scourge of the tongue' is the taunting of insults offered. They strike the righteous 'with the scourge of the tongue,' who pursue their deeds with mockery. For oftentimes the tongue, while it utters jibes, recalls from a good deed, and puts itself out like a scourge, in that it cuts the back of the cowardly soul. …

Morals on the Book of Job, Book VI ↗

Thomas Aquinas

Corporeal life is also taken away by natural death, but this does not figure among the trials since the nature of man demands this. However, sometimes there is a personal danger which consists in the loss of the honor which he enjoys in civil life. About this he says, "You shall be hidden from the scourge of the tongue." The scourge of the tongue is the detraction of someone seriously trying to destroy another's reputation. …

Commentary on Job ↗