Kommentar zu Schemot 16:30

וישבתו העם, from that day onwards the people made it a rule to observe rest ביום השביעי, every seventh day.

R. Yehoshua says: He said to Israel: If you keep this Sabbath the Holy One Blessed be He is destined to give you three festivals: the festival of Nissan (Pesach), the festival of Sivan (Shavuoth), and the festival of Tishrei (Succoth). When they heard this, they accepted it and rested. R. Eliezer Hamodai says: The L rd said to them: If you keep this Sabbath, I am destined to give you six goodly "measures": Eretz Yisrael, etc. (see above). R. Elazar says: If you keep this Sabbath, you will be saved from three dire punishments: the pangs of (the advent of) the Messiah, the day of Gog and Magog, and the day of the great judgment. And when they heard this, they accepted it and rested.

וישבתו העם ביום השביעי, “the people remained inactive on the seventh day.”