The Crowns are Returned
In the Gemara (שבת פח ע"א) Chazal tell us that before Mattan Torah, when the Yidden were offered the Torah, they immediately exclaimed נַעֲשֶׂה וְנִשְׁמָע. As a reward for this enthusiastic response, six hundred thousand malachim descended and adorned each Yid with two crowns, one for נַעֲשֶׂה and another for נִשְׁמָע.
However, when Klal Yisrael sinned with the Chet Ha'egel the crowns were taken away from them. As it says וַיִּתְנַצְּלוּ בְנֵי יִשְׂרָאֵל אֶת עֶדְיָם מֵהַר חוֹרֵב (שמות לג ו) - and Klal Yisrael removed their jewelry, i.e. the crowns they had received at Sinai. The crowns were then passed on to Moshe.
The Arizal teaches, that every Shabbos these crowns are returned to us! We revert back to the state we were in when we proclaimed נַעֲשֶׂה וְנִשְׁמָע!
The Oheiv Yisrael sees a reference to this in the first pasuk of Parshas Vayakheil where it says that Moshe gathers אֶת כָּל עֲדַת בְּנֵי יִשְׂרָאֵל - the whole congregation of Yisrael, and there after instructs them with the mitzvah of Shabbos. The Oheiv Yisrael points out that עֲדַת shares a root with עֶדְיָם, the word used for the crowns in Parshas Ki Sisa.
The Chida in his sefer P'nei Dovidoffers the same interpretation of this pasuk, adding beautifully, by commenting on the words that we say in davening, יִשְׂמַח מֹשֶׁה בְּמַתְּנַת חֶלְקוֹ Let Moshe rejoice in his portion. He explains that Moshe's cause for happiness on Shabbos is that now he has only his own crowns as a gift. He does not desire the crowns that belong to Yisrael; on Shabbos he rejoices that Klal Yisrael have their crowns returned to them, and he has only חֶלְקוֹ - his own lot.
