Daily Mitzvah (Rambam)

When a person comes to a Rebbe and seeks his counsel and assistance in dealing with a spiritual malady, the Rebbe must first find the same blemish, if only in the most subtle of forms, in his own soul; only then can the Rebbe help him to refine and perfect his self and character. This is the deeper significance of that which our sages have said, "the faults of a generation rest with its heads and leaders."

  –Rabbi Yosef Yitzchak of Lubavitch