"the voice of the words"
The rabbis examine the scripture that tells of Moses' admonitions to Yisrael where he reminds them that God spoke to them out of the midst of the fire and that they heard the voice of the words. The people heard the words but saw no form, and we learn that "a form" is an inner voice, namely Binah. Rabbi Elazar talks about the second Torah, Deuteronomy, that Moses spoke himself. He analyzes all the voices, the inner voice, the outer voice and the voice of the words, and the words and the speech that came out and spoke from within the fire. We learn that Yisrael did not want to hear directly from God but only through Moses; this weakened the power of Moses and the power of Malchut. Lastly Rabbi Elazar says that if a person does a wicked deed but has no evil intention he is not punished.