A simple person should not try to rejoice on the same level as the great man, rather, the great man should try to rejoice like a simple person. Yet how is that possible when, after all, the scholar does know Torah and he is happy in that knowledge?
We tell him that he needs to have simple faith that despite his depth of learning and rarified style of inquiry, his great understanding does not reach the essence of Torah. The essence of Torah is hidden from the eyes of all creation; it is the essential enjoyment of Hashem in His own essence.
The simple Jew brings a wedding as the metaphor for Simchas Torah. So too, the giving of the Torah is described as the wedding of the Holy One, Blessed be He, with the congregation of the children of Israel.
A wedding is an example of great simcha. As such, it breaks all barriers to the point where one can achieve those levels of Torah that remain beyond him, higher and higher and with great strength.
According to a maamar of the Rebbe [Simchas Torah 5731], our rejoicing on Simchas Torah is over the second tablets Moshe received on Yom Kippur when Hashem accepted our Tshuva.
