Arachin 15 - How Bad is Bad Talk?
In the laws of a violator and seducer there are also elements of leniency and stringency. Whether one seduced or violated the daughter of the most prominent family of Kohanim or the lowest family of Israel, he pays fifty shekels. By contrast, the payments for humiliation depends on who humiliated and who was humiliated.
One who defames his new wife may face a leniency and a stringency: whether he defamed the most prominent maiden in the priesthood or the humblest maiden among the Jewish people, he pays a hundred shekels.
We thus see that one who speaks evil with his mouth is worse than one who performs an evil deed. Similary, the decree that the Jews should not enter Israel and stay in the desert for another forty years was sealed on account of the bad words they said about the Land of Israel. The Torah said, "They tested Me these (literally, this) ten times", and the word "this" tells that these bad words were the reason. If one is punished so for talking about land and rocks, then now much more when talking about his fellow.
Art: Jean-Baptiste Madou - The Gossips