"Speak now (na) in the ears of the people" (Exodus 11:2). The word na means nothing but a term of request. The Holy One, blessed be He, said to Moses: I ask of you, say to Israel, I beg of you, ask of the Egyptians vessels of silver and vessels of gold, so that the righteous one [Abraham] should not say, "and they shall serve them, and they shall afflict them" (Genesis 15:13) He fulfilled with them, but "and afterward they shall come out with great wealth" He did not fulfill with them. They said to him: Would that we might go out with our own bodies! To what may the matter be compared? To a man who was imprisoned in jail, and they said to him, Tomorrow your master will release you and give you much money. He said to them, I beg of you, take me out now, and I am not asking for money.
Speak Please in the Ears of the People to Ask Egypt for Silver
Yalkut Shimoni on Torah 186:7
(שמות יא ב) דַבֶּר נָא בְּאָזְנֵי הָעָם. אֵין נָא אֶלָּא לְשׁוֹן בַּקָּשָׁה, אָמַר לוֹ הַקָּדוֹשׁ בָּרוּךְ הוּא לְמֹשֶׁה, בַּקָּשָׁה מִמְּךָ, אֱמֹר לָהֶם לְיִשְׂרָאֵל, בְּבַקָּשָׁה מִכֶּם, שַׁאֲלוּ מִמִּצְרַיִם כְּלֵי כֶסֶף וּכְלֵי זָהָב, שֶׁלֹּא יֹאמַר אוֹתוֹ צַדִּיק (בראשית טו, יג) "וַעֲבָדוּם וְעִנּוּ אֹתָם" קִיֵּם בָּהֶן, "וְאֲחַרֵי כֵן יֵצְאוּ בִּרְכֻשׁ גָּדוֹל" לֹא קִיֵּם בָּהֶן. אָמְרוּ לוֹ, וּלְוַאי שֶׁנֵּצֵא בְּעַצְמוֹתֵינוּ. מָשָׁל לְמַה הַדָּבָר דּוֹמֶה, לְאָדָם שֶׁהָיָה חָבוּשׁ בְּבֵית הָאֲסוּרִין, אָמְרוּ לוֹ, לְמָחָר מַתִּיר אוֹתְךָ רַבְּךָ וְנוֹתֵן לְךָ מָמוֹן הַרְבֵּה, אָמַר לָהֶם, בְּבַקָּשָׁה מִכֶּם הוֹצִיאוּנִי עַכְשָיו וְאֵין אֲנִי מְבַקֵּשׁ מָמוֹן.