The revelation at Sinai was undoubtedly intense and all-encompassing. But one verse in the Torah describing the experience suggests that the Children of Israel had a sensory experience of an unrivaled level.
All the people witnessed the thunder and lightning, the blare of the shofar and the mountain smoking; and when the people saw it, they fell back and stood at a distance. Exodus 20:15
The word in this verse that is usually translated as ‘witnessed’ or ‘perceived’ is ro’im (רֹאִים), which literally means “they saw.” This verse, taken at face value, implies that at Mount Sinai, the Children of Israel literally saw the thunder in what modern science refers to as synesthesia, a fancy name for when you experience one of your senses through another. At Sinai, this came as a result of sensory (and spiritual) overload. Having a direct connection with the Creator required an expansive consciousness that connected the individual with all of reality.
Rashi explains that this experience was a one-time, never-again miracle that is impossible under normal circumstances. This happened because the event was a miraculous transcendent one-time event; hearing the voice of God.
It is taught that the thunder and lightning which accompanied the giving of the Torah at Sinai were not localized, but were rumblings and flashes that permeated all of creation when the Torah was given.
Furthermore, the Midrash says that at Sinai, the Torah was heard in all 70 languages of the nations. The Torah was the blueprint for creation and was intended to unite mankind under one God but, at the same time, each individual experienced it in his own way. Each individual ‘saw’ the unity of creation. In order to function as a light unto the nations and a kingdom of priests, teaching the Torah to the world, the Jews had to receive the Torah in every language.
The experience of Sinai was so far beyond the normal human experience that the nation asked not to continue to go through it, fearful that it was simply too much for them to bear. They begged Moses to act as an intermediary “lest we die” (Exodus 20:16). It was important for them to experience, however, in order to fully receive the Torah, since the Torah is not something we simply but rather something we live. In our own lives as well, we must experience God with all of our senses in order for us to fully receive the Torah. Performing mitzvot (commandments) help us do that as they connect heaven and earth, bringing the Torah into our daily lives.
Mount Sinai was not the first time that God appeared in a fiery form. In the verse from Exodus cited above, the word that is translated as ‘lightning’ is lapidim (לַּפִּידִם), which literally means ‘torches.’ This references to torches at Sinai is reminiscent of the vision in which God appeared to Abraham Covenant of the Parts:
When the sun set and it was very dark, there appeared a smoking oven, and a flaming torch which passed between those pieces. Genesis 15:17
The covenant with Abraham, the father of nations, changed him and all of his descendants, just as the experience at Sinai changed Israel; binding us to God and his Torah for all time.