EXOD77 A teacher should respect his students. … A teacher must constantly learn. Moshe was bidden by the Almighty to show two signs to the Jews that he was to lead them. Shmos 4:1-3. His staff turned into a serpent and his hand became leprous when he removed it from his bosom. Rashi explains that the snake indicated that Moshe slandered the Jews (like the serpent of old) and that the leprosy was a punishment for having suspected people. In essence Moshe was saying, "Look, I've suspected you wrongly and I've spoken loshon hara against you." The question arises what kind of claim to leadership was this declaration? Rabbi Eliyahu Meir Bock, Rosh Hayeshiva of Telshe, explains that Moshe demonstrated he had indeed made mistakes, but he was ready to learn. Rabbi Chaim Dov Keller, Rosh Hayeshiva of Telshe in Chicago, Jewish Observer, Sept. 1977.