However that Friday, Erev Shabbos, Bnei Yisrael gathered their family’s portions of Mann, but when they brought it home they found that their portions doubled.
Confused, they asked Moshe. “Why is this day different from all other days?”
“What is the meaning behind this double portion?”
“Moshe Rabbeinu, I am all confused. Didn’t you instruct us not to store any Mann for the next day?”
“Tomorrow is an exception,” Moshe explained. “It’s Shabbos, a holy day and a day of rest. Let no man leave his place on the 7th day. No Mann will fall on Shabbos, but the Mann you gathered today will be enough to feed your families for two days – one for today on Friday, and the other for the Shabbos meals.”
Bnei Yisrael noticed something else special about the Mann that day. Each flake was “sandwiched” between two layers of dew.
To commemorate the miraculous double portion and two layers of dew, every Shabbos, Jews throughout the world begin their Shabbos meals with making a blessing on two loaves of Challah, called Lechem Mishneh.
In addition, the two Challahs are “sandwiched” between a nice Challah-tray and a beautiful Challah-cover. This also reminds us of the two layers of dew “sandwiched” between the Mann.