en_tn_condensed/deu/18/16.md

This is what you asked

Here "you" refers to the Israelites at Mount Horeb about 40 years earlier.

at Horeb on the day of the assembly

"on the day you gathered together at Horeb"

on the day of the assembly, saying, 'Let us not hear again the voice of Yahweh our God, nor see this great fire anymore, or we will die.'

This has a quotation within a quotation. A direct quotation can be stated as an indirect quotation. Alternate translation: "on the day of the assembly when you said that you did not want to hear the voice of Yahweh our God, nor see his great fire anymore, because you were afraid that you would die." (See:rc://en/ta/man/translate/figs-quotesinquotes and rc://en/ta/man/translate/figs-quotations)

Let us not hear again the voice of Yahweh our God

Here Yahweh is represented by his "voice" to emphasize what he says. Alternate translation: "Let us not hear Yahweh our God speak again" (See: rc://en/ta/man/translate/figs-synecdoche)