G‑d descended upon Mount Sinai, to the top of the mountain. And G‑d called Moses to the top of the mountain, and Moses ascended. (19:20)

If G‑d descended from the supernal heights, couldn’t He come down just few thousand feet further? Why trouble a man of eighty to climb to the top of the mountain?

Yet therein lies the essential nature of man’s comprehension of Torah. G‑d is infinite and undefinable. Torah is His wisdom and will—by definition, ungraspable by the finite mind of man. The notion that the human intellect can relate to the divine truth, or even meet it halfway, is ludicrous. It is only because G‑d gave us the Torah, only because He chose to suspend the line He drew at creation separating the finite from the infinite, that we can access His communication to man.

But the Almighty desired that man’s understanding of Torah not be a gift from above, but the result of a combined effort, the issue of a union between the human mind and the mind of G‑d. Man must give it his intellectual all, and apply to the utmost the powers invested in his brain of flesh. And when he attains the peak of his finite mountain, there is G‑d with His gift of absolute truth.

—From the teachings of Chassidism

The Lubavitcher Rebbe, of righteous memory, related:

Rabbi Yechezkel Landau, the famed author of Noda B’Yehudah, served as the rabbi of Prague from 1754 to 1793. Once, a group of scholars who wished to contest his rabbinic qualifications presented him with a series of questions in Torah law. These fictitious “cases” were carefully constructed to be as complex and as misleading as possible, so as to ensnare the rabbi in their logical traps and embarrass him with an incorrect ruling.

Rabbi Yechezkel succeeded in resolving all the questions correctly—all, that is, but one. Immediately his detractors pounced on him, demonstrating how his verdict contradicts a certain principle of Torah law.

Said Rabbi Yechezkel: “I am certain that this case is not actually relevant, and that you have invented it in order to embarrass me. You see, whenever a man of flesh and blood is called upon to decide a matter of Torah law, we are confronted with a basic dilemma: how can the human mind possibly determine what is G‑d’s will? The dos and don’ts of Torah are the guidelines by which the Almighty desires that we order our lives. How is it that the finite and error-prone intellect is authorized to decide such divine absolutes?

“But the Torah itself instructs that the Torah ‘is not in heaven,’ but has been given to man to study and comprehend;1 and that whenever a question or issue is raised, it is man, employing his finite knowledge and judgement, who must render a ruling. In other words, when a person puts aside all considerations of self and totally surrenders his mind to serve the Torah, G‑d guarantees that the result will be utterly consistent with His will.

“However,” concluded Rabbi Yechezkel, “this guarantee applies only to actual events, when a rabbi is called upon to determine what it is that G‑d desires to be done under a given set of circumstances; but not if his personal honor is the only issue at hand. Had you presented me with a relevant question, I know that I would not have erred, since I approached the matter with no interest or motive other than to serve the will of G‑d. But since your case was merely a hypothetical question designed to mislead me, my mind was just like every other mind, great and small alike—imperfect and manipulable.”