The original language speaks of “the voice of the first sign” and “the voice of the latter sign.” The implication is that the signs that Moses would perform would speak to the people, just like Psalm 19:1–14 says that the heavens declare something to us. This kind of language teaches us that God was intentionally sending a message to Moses and the people through the signs.
8 “If they will not believe you,” God said, “or listen to the first sign, they may believe the latter sign.