9 Heb “Lord Yahweh.” The translation follows the ancient Jewish tradition of substituting the Hebrew word for “God” for the proper name Yahweh in this compound name. See the study note on v. for the substitution of “Lord” in a similar kind of situation.
10 Heb “Behold, I do not know how to speak.” The particle הִנֵּה (hinneh, commonly rendered “behold”) often introduces a speech and calls special attention to a specific word or the statement as a whole (see §40.2.1).
11 The words “well enough for that” are implicit and are supplied in the translation for clarity. Jeremiah is not claiming an absolute inability to speak.
12 Heb “I am a boy/youth.” The Hebrew word can refer to an infant (Exod 2:6), a young boy (1 Sam 2:11), a teenager (Gen 21:12), or a young man (2 Sam 18:5). The translation is deliberately ambiguous since it is unclear how old Jeremiah was when he was called to begin prophesying.

In other versions

Then I said, “Ah, Lord God! Behold, I do not know how to speak, for I am only a youth.”

“Alas, Sovereign Lord,” I said, “I do not know how to speak; I am too young.”

But I protested, “Oh no, Lord God! Look, I don’t know how to speak since I am only a youth.”

“O Sovereign Lord,” I said, “I can’t speak for you! I’m too young!”

Then I said, “Ah, Lord Yahweh! Look, I do not know how to speak, for I am a youth.”

Then said I, Ah, Lord God! behold, I cannot speak: for I am a child.

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