Sefer Derachav V’Sichosav shel Hachafetz Chaim relates the following in the name of R’ Tuvia Rottenberg zt”l:
A dispute once broke out in the Radin Yeshiva over a certain matter, and the yeshiva was divided into two camps. When the Chofetz Chaim heard about it, he was very upset. He walked into the bais medrash and gave a tear-filled drasha for two hours about how terrible machlokes is.
Amongst his words, he said, “The Rambam says that those who speaks lashon hara have no share in the World to Come. The reason I did not quote this in my sefer is because I did not want to include such a sharp statement. But the fact remains that it is the truth!”
He concluded his drasha by saying, “I love those who learn Torah very much, but I still must tell them that it would be better to close down 70 yeshivos than to have people speaking lashon hara in them!”
