Halakhah sur Le Deutéronome 5:11

5) And the speaker of lashon hara also transgresses (Devarim 8:11): "Take heed unto yourself lest you forget the L–rd your G–d," which is an exhortation to the proud of spirit, for since he mocks and ridicules his friend, he apparently considers himself wise and "a man among men." For if he knew his own faults, he would not deride his friend. And the statement of Chazal in Sotah (4b) on the severity of the sin of pride is well known, viz.: Because of it his dust does not wake for the resurrection, he is considered an idolator, the Shechinah wails over him, and he is called "an abomination." And, especially, if in shaming his friend he honors himself, he certainly transgresses this negative commandment, aside from our Rabbis' (in their holy spirit) having "cut him off" from the world to come, saying (Yerushalmi Chagigah 12:1): "One who honors himself by the shame of his friend has no share in the world to come."