Albert Barnes Commentary Exodus 16:29

"See, for that Jehovah hath given you the sabbath, therefore he giveth you on the sixth day the bread of two days; abide ye every man in his place, let no man go out of his place on the seventh day." — Exodus 16:29 (ASV)

Abide you every man in his place - The expression in Hebrew is unique and seems almost to enjoin a position of complete repose: the phrase “in his place” is literally “under himself,” as one sits in Eastern cultures with his legs drawn up under him.

The prohibition must, however, be understood with reference to its immediate object: they were not to go out from their place in order to gather manna, which was on other days outside the camp. The spirit of the law is sacred rest. The Lord gave them this Sabbath as a blessing and privilege. It was made for man (Mark 2:27).