At the giving of the Torah, the Israelites heard the voice of God Himself. The Sages depict the tremendous effect of the speech of God.

Rabbi Yehoshua ben Levi said: Each and every utterance that emerged from the mouth of the Holy One, blessed be He, caused the entire world to be filled with fragrant spices….

And Rabbi Yehoshua ben Levi said: Each and every utterance that emerged from the mouth of the Holy One, blessed be He, caused the souls of the Israelites to depart from their bodies, as it is stated: “My soul had departed with His speaking” (Song of Songs 5:6). Since their souls left from the first utterance, how did they receive the second utterance? God rained the dew upon them that, in the future, will revive the dead, and it revived them.

The Holy One, blessed be He, may His name and might be blessed, when He pronounced His speech, the voice was divided into seven voices, and from seven it split into the seventy languages of the seventy archetypal nations, so that everyone would understand. (Shabbat 88a; Midrash Tehillim [Buber] 68)