רב לכם בני לוי In the chapters that we read this week in parshat Korah, both Moses  and the congregation of Korach accuse each other of being the rav of the "kelipa"[that is rav *(religious teacher) of the Dark Side] [This is how Rav Isaac Luria explains these verses]. For in the congregation of Korah were the greatest teachers of Torah in that generation as the second Rashi in the Parsha explains--that they were the 250 heads of the sanhedrins

[background note--Korah and his group were against Moses [Moshe], At  the beginning of their revolt they said to moses [''we have had enough of you children of Levi. Literally that is "That is too much of you Children of Levi" But the language also can mean, "You have a Rav (of the kelipa)" and Moses threw at them the exact same accusation "You have a Rav (of the kelipa)"