4. Listening to backbiters is a great sin.

Certain experiments prove that magnets possess a mysterious and wonderful power. According to Jerome Cardan, if you rub a dagger with a magnet, those it pierces afterwards will not feel it: "In the home of Dr. Lawrence Guascus I saw a needle or a metal point rubbed with a magnet; one could then stick the needle or point into any part of the body without causing any pain. This seemed incredible to me, and I wanted to make sure it was true. So I took a needle, rubbed it with a magnet and stuck it into my arm. I felt the needle's presence when it had penetrated completely, but I felt no pain whatsoever. In order to be really sure I turned the needle, still stuck in my arm, in every direction. But I felt nothing and shed not a drop of blood. Afterwards, only the point where the needle had entered could be seen." Cardan adds that Alexander of Verona was the first to perform this experiment, in Milan: he rubbed a sword with oil in order to be able to wound and heal whoever he wished without any pain.
Backbiting resembles that dagger perfectly. You thrust it in, it enters and causes a wound to three people at once: the backbiter, his listener and the person he backbites. The most seriously wounded one of all, the backbiter, feels absolutely nothing.
But we have already talked about him in the preceding chapter. Let us now take a look at his listener.
We will show what an enormous sin is committed, not only by backbiters, but by those who listen to them willingly, and we will enlighten the backbiter and his listeners at the same time.

I.
Homer, the prince of poets, relates how Ulysses acted with his seafaring companions. That prudent fellow knew that the sweet, languorous siren's song usually softened men and then lured them into the depths of the sea. To safeguard himself and his friends on their way through this hazardous zone, he had them stop their ears with wax and bind him to the ship's mast until the moment of danger had passed. Thus there are dangers for the ears as well as for the eyes, and one must make sure that they are hermetically sealed.
It is nothing new to encircle fields and gardens with hedges, but it may seem strange to do so for our ears. Yet the Holy Spirit judges it necessary. "Hedge in your ears with thorns," He says, "listen not to the wicked tongue, and make doors and bars to thy mouth." (1) The Holy Spirit does not want this hedge protecting our ears to be a flower hedge, but a spiny thorn hedge, to keep the backbiter away.
(1) Sir 28:28
Hedges protect fields against animals and gardens against thieves. So must we have thorns to guard our ears against backbiters. When they come near, they run into brambles when you show absolute disapproval of what they say. Take heed not to lend an ear and listen willingly to them. On the contrary, let them see that you do not care for this sort of conversation. For if you listen willingly to everything others whisper in your ear, what sort of people will you be compared to?
Two dogs gnawing on the same bone is a rare sight, practically a phenomenon. Now, if you see a backbiter and his listener in perfect agreement, the one to speak and the other to give ear, would you not say that they look exactly like two dogs gnawing on the same bone? Two evil people who analyze the behavior of a good man weigh him, sift him and grind him with their words. This is truly the equivalent of chewing bones and cracking them between one's teeth.
Saint Bernard discusses the gravity of the sin that both the backbiter and his listener commit. "I would have difficulty deciding which of them is more damnable," he says, "he who backbites or he who listens to the backbiter. Even if we excuse it as wit or banter, every jesting word must be banished not only from our mouth, but also from our ears." (2) Another man has cleverly remarked, "The devil dances in the backbiter's mouth and in his listener's ear." If you lend a favorable ear to a gossiper and spur him on to speak, you incite him to proceed with still greater freedom, boldness and excess. "The burglar who holds the bag and the thief who slips in the spoils are equally guilty," says the proverb. The perpetrator and the consenter are both deserving of the same punishment; the same is true of the backbiter and his listener. Saint Thomas Aquinas teaches, "He who hears someone backbiting and does not oppose him appears to approve the author, thus participating in his sin." (3) Saint Jerome speaks in the same vein: "Beware that your restless ears and tongue do not listen to or engage in backbiting." (4)

(2) Saint Bernard, De consideratione, Book 2, Chapter 13
(3) Saint Thomas Aquinas, Summa Theologica, Part II, Section II, Question 83, Article 2.
(4) Saint Jerome, Epistolora ad Nepotium, ad Rustic

"I don't backbite," you may say, "but how can I stop others from talking?" Look at what sort of pretexts we invent to excuse our sins! Tell me then: If you were passing in front of someone's house, and his dog came running after you barking and ready to bite you, would you be pleased if his master's servant did not prevent him? And if he even encouraged the dog to press on after you, would you be able to contain your indignation? Now let's change the circumstances: When you listen quietly to a backbiter, you are not only letting this dog attack passers-by and bite them, but you are urging him on, for you lend credence to what he says.