36 Heb “And Moses said.”
37 When he was younger, Moses was confident and impulsive, but now that he is older the greatness of the task makes him unsure. The remainder of this chapter and the next chapter record the four difficulties of Moses and how the Lord answers them (11–12, 13–22; then 4:1–9; and finally 4:10–17).
38 The imperfect tense אֵלֵךְ (’elekh) carries the modal nuance of obligatory imperfect, i.e., “that I should go.” Moses at this point is overwhelmed with the task of representing God, and with his personal insufficiency, and so in honest humility questions the choice.

In other versions

But Moses said to God, “Who am I that I should go to Pharaoh and bring the children of Israel out of Egypt?”

But Moses said to God, “Who am I that I should go to Pharaoh and bring the Israelites out of Egypt?”

But Moses asked God, “Who am I that I should go to Pharaoh and that I should bring the Israelites out of Egypt?”

But Moses protested to God, “Who am I to appear before Pharaoh? Who am I to lead the people of Israel out of Egypt?”

But Moses said to God, “Who am I that I should go to Pharaoh and that I should bring the Israelites out from Egypt?”

And Moses said unto God, Who am I, that I should go unto Pharaoh, and that I should bring forth the children of Israel out of Egypt?

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