Did Moshe have a speech impediment?
From a simple reading of the Torah verses and Talmudic teachings, it would seem that he did. However, we’ll see that’s not necessarily the case.
When G-d charges Moshe through the burning bush to demand that Pharaoh let the Jewish People go, Moshe replies, “I beseech You, O Lord. I am not a man of words...for I am heavy of mouth and heavy of tongue” (Ex. 4:10).
Moshe seems to be demurring G-d’s command because of an inability to speak well enough to convince Pharaoh of such a great request.
Similarly, Talmudic sources also seem to indicate that Moshe had a speech impediment.
One teaching describes that Pharaoh suspected Moshe wanted to usurp his throne. He placed before the lad his glittering crown of gold on one side (which if he took, he’d be put to death) and glittering red coals on the other. Moshe went to reach for the crown, but an angel turned his hand toward the fiery coals instead. Moshe instinctively cooled his burning fingers in his mouth, which then impaired his speech.
Another tradition informs us that Moshe could not pronounce certain of the Hebrew letters – namely bet, vav, mem and peh.
However, on the other hand, we also find that Moshe had a very highly developed “power of speech”. When Moshe slew the Egyptian taskmaster who was mercilessly beating the Jewish slave, our sources explain that he did so by pronouncing a Divine name to incur G-d’s judgment over the person. (This is based on a possible reading of the continuation of the verses, where the next day, when rebuking a Jew who was beating his fellow Jew, the offender replied to Moshe, “Will you kill me by speaking as you did to the Egyptian?”)
And even regarding G-d’s sending Moshe to Pharaoh, after Moshe recalls his so-called speech impediment, G-d replies, “Is there not Aaron your brother, the Levite? I know that he will surely speak, and behold, he is coming forth toward you....You shall speak to him, and you shall put the words into his mouth....And he will speak for you to the people, and it will be that he will be your speaker, and you will be his leader”. If Moshe was such a bad talker, how was he to put the words in Aaron’s mouth?
The explanation is as follows: Moshe did not have a speech impediment in the normal sense of the word. Rather, he was so spiritually elevated that he was not able to communicate in a way that average people could understand. This is what is meant by Moshe being heavy of mouth and tongue – the regular instruments of speech were too clumsy and course to express his level of lofty comprehension. So G-d sent him Aaron who was elevated enough to comprehend Moshe but “low” enough to convey his ideas to other people. This is the meaning of Aaron “coming toward” Moshe and in turn speaking for him to the people. And it is for this reason that Aaron is described as the speaker and Moshe as the “leader” where the Hebrew word used is “elohim”. Moshe is so elevated that he is likened to Aaron what G-d is to Moshe. As G-d later communicated the Torah through Moshe, Moshe communicates G-d’s message through Aaron.
So in this light, how are we to explain the teachings regarding Moshe’s burning his mouth and his inability to pronounce certain of the letters?
Moshe was certainly destined to replace Pharaoh. However, as a youth raised in his palace, he could have indulged in the glitter of Egyptian wealth until he himself gained physical control of the crown. But this would not have ensured the physical and spiritual redemption of the Jewish People. For this Moshe would have to rise to great spiritual mastery. This is represented by the challenge of choosing the golden crown or the fire, where fire represents spiritual fervor. Had Moshe chosen the material manifestation of kingship, his mission would have been terminated. The spiritual force within him pushed him toward the fire (despite having all the sensuality of the fleshpots of Egypt at his fingertips) for which he ultimately merited the revelation of the burning bush, but which simultaneously impeded his ability to communicate with ordinary people.
Similarly, this is also the deeper meaning of the teaching regarding Moshe’s inability to pronounce certain of the letters. The Hebrew letters are divided into five groups based on where they’re enunciated: throat, palate, tongue, teeth, lips. Since the letters make up the Torah, these different groups correspond to different levels of Torah ideas where the guttural letters are the deepest and those expressed by the lips correspond to the more external meanings. The fact that these labial letters – bet, vav, mem, peh (“bumaf”) — are specifically the ones Moshe is described as having difficulty pronouncing refers to the way in which Moshe’s extremely deep level of comprehension impeded his ability to communicate such subliminal understandings to the outside world!