Every school child knows that Moses had a speech impediment. Rashi claims that it was a physical problem, while modern psychologists suggest that perhaps he stuttered or had a psychological issue due to being taken from his biological mother at a young age.
These explanations, however, don’t explain why the term aral s’fatayim is used in regards to Moses’s reluctance to speak. Why doesn’t the Torah simply say that his mouth was disfigured or his speech was broken? The use of the symbolically-laden word “uncircumcised” cries out for interpretation. (In the previous parashah Moses is almost killed for not circumcising his own first-born son.)
Moses seems to have an unresolved issue regarding circumcision. Whenever the word arises, he needs someone else (his brother or his wife) to step in and support him. Perhaps he realises that, while circumcision is a physical act, brit milah is much more. It symbolises identification with the Jewish people which he finds challenging because of his complicated childhood.
Part of Moses’s brilliance as a leader is that he has dual identity, birthed/nursed by a Hebrew mother, and named/raised by an Egyptian mother. Because both cultures are part of him, perhaps he doesn’t feel wholly Israelite. Perhaps he is saying that his lips, which he will need to use to redeem the Israelites, are not fully Israelite themselves. So he needs his brother to speak to the man who served as a surrogate (grand)father to Moses for so many years.
This is both the power and the challenge of living in two cultures: how to speak out against Pharaoh, who tried to kill us, while continuing to express our connection and love for Pharaoh’s daughter, who befriended and saved us. It is a message that speaks through the centuries to British Jews today. Once again, Moses is the greatest teacher who lived.