In Reb Nosson‘s dairy, he describes the scene of his meeting some emissaries from Vilna, while on his way to the Land of Israel (April 1822 in Odessa):
“And I began to speak with them about emunas chachomim (believing in the sages), being that I was convinced that surely they at least have some faith in the Gaon of Vilna, for it is by his name that they are called and associated. But they immediately retorted, especially one of them who was the main speaker with whom they all agreed, saying such and such, ‘I should have faith in a person?’ and they said so with a tone of incredulity. He spoke in this manner with me, and they all agreed with him. And I began to argue with him, saying, ‘If so, what is emunas chachamim?’ But they would not lend their ears to hear me at all, and they answered words of foolishness and vanity, which were related somewhat to heresy. For truly one who lacks emunas chachomim – even their faith in G-d is incomplete, as is explained in our teachings at length.
It was then that I clearly saw the difference between the Hassidim and the Misnagdim, for I saw that even in their own sage, whom they know was exceedingly learned and exceedingly pious, even in he they have no faith. And later on I said so to them explicitly: ‘I thought that [even] if you don’t have faith in the great Hassidic tzaddikim, at least you would believe in your own sage. But now I see that you actually have no faith at all“.
(Yemei Moharnat 242).
In this week’s Torah portion Judah approaches Joseph and pleas with him to release Benjamin from impending slavery. Reb Nosson (Hilchos Taanis 4) writes that this episode symbolizes the Jewish people (who are called Jews after Judah) approaching the true tzaddik (symbolized by Joseph) and begging his forgiveness for selling him, which represents our lack of emunas chachamim.
Many people have a hard time believing in the Sages. They’re ok with the Divinity and perfection of the Torah but why should we heed the words of the sages, especially later sages, with the same regard? Why must we believe in the tzaddik? Maybe he’s a great person but he’s only human and he makes mistakes, so not everything he says should be followed.
The answer is that this belief is critical to our own development. The reason why people don’t believe in the near perfection of the tzaddikim is because they look at themselves, see their own shortcomings, and they can’t imagine that there is a person in the world who overcame every obstacle, step by step, and achieved true greatness. They think if I can’t do it, and pretty much everyone I know is struggling with this too, then it’s impossible. We must see things from the exact opposite perspective. We must believe that true greatness is attainable, and has been attained by these near-angels, so that we can fully believe in our own ability to become great. If we are always skeptical of everyone else, never believing that someone can be superior to most people, then how can we ever believe in ourselves, and reach the levels that we are destined to reach? Believing in the tzaddikim is believing in man’s ability (and our own ability) to soar to unimaginable heights. This is a critical part of Avodas Hashem.