Based on this calculation, the 15th of Tishrei (the first day of Sukkot) was the next day, on Sunday. That would have been the day they began the work on the Mishkan since the donations were accepted until Friday and the work on the Mishkan couldn’t be done on Shabbat. According to the Vilna Gaon, the Clouds of Glory, which had departed when the Jewish people made the golden calf, returned on that day in honor of the building of the Mishkan. This is why the 15th of Tishrei was designated as the holiday of Sukkot when we commemorate the Clouds of Glory.
Explains the Opinion of the Roke’ach
The Roke’ach writes that the Clouds of Glory encompassing the Jewish camp turned it into a private domain. The Talmud says that the Jewish people were knocked back 12 mil (approximately 7 miles) when they heard the first of the Ten Commandments and that the angels had to assist them to return to the Mountain. Since the Torah was given on Shabbat (see above), how were they allowed to travel this distance on Shabbat which is beyond the Techum Shabbat (Shabbat boundary)? He explains that the Clouds turned the entire area into a private domain and that, as such, this travel was permitted.
This opinion is questioned since the Talmud says (quoted above) that Moshe instructed the people to stop bringing the donations in order not to carry on Shabbat. If the Clouds of Glory turned the camp into a private domain, carrying these donations should have been permissible on Shabbat.
Based on the above, however, we can explain this matter, as the day on which Moshe told the Jewish people to stop donating was the Shabbat, the 14th of Nissan, one day before the Clouds of Glory returned (in the 15th of Nissan). Therefore, carrying was forbidden on that day after all.
