Another interpretation of "saying" [lemor]: Go out and say it to Israel, and bring Me back word of what they say. And from where do we know that Moses would bring words back before the Almighty? As it says, "And Moses brought back the words of the people to the LORD" (Exodus 19:8). And what were the words of the people? They said, "All that the LORD has spoken we will do and we will hear" (Exodus 24:7). And from where do we know that the Omnipresent conceded to their words? As it says, "And the LORD said to me: They have done well in all that they have spoken" (Deuteronomy 5:25).
Moses Carries Israel's Answer Back Up to God
Yalkut Shimoni on Torah 285:5
דָּבָר אַחֵר לֵאמֹר, צֵא וֶאֱמֹר לָהֶם לְיִשְׂרָאֵל וַהֲשִׁיבֵנִי מַה הֵן אוֹמְרִים. וּמִנַּיִן שֶׁהָיָה מֹשֶׁה מֵשִׁיב דְּבָרִים לִפְנֵי הַגְּבוּרָה שֶׁנֶּאֱמַר (לעיל פסוק ח) וַיָּשֶׁב מֹשֶׁה אֶת דִּבְרֵי הָעָם אֶל ה'. וּמֶה הָיוּ דִּבְרֵי הָעָם, אָמְרוּ "כֹּל אֲשֶׁר דִּבֶּר ה' נַעֲשֶׂה וְנִשְׁמָע", וּמִנַּיִן שֶׁהַמָּקוֹם הוֹדָה לְדִבְרֵיהֶם, שֶׁנֶּאֱמַר (דברים ה, כה) "וַיֹּאמֶר ה' אֵלַי הֵיטִיבוּ אֶת אֲשֶׁר דִבֵּרוּ".