Exodus Chapter 16    

“the fifteenth day of the second month.” The Israelites left Egypt on the fifteenth day of the first month, Nisan, so by the fifteenth day of the second month they had been traveling one month.

“Let no one leave any of it until the morning.” The manna would spoil overnight, and since people could gather it every day, there was no need to try to save any of it for the next day, except on the Sabbath.

“and when the sun grew hot, it melted.” The manna was free for the taking, but it did not encourage laziness because it melted when the sun got hot, which occurred quite early in the morning. People needed to get up and get to work gathering it if they wanted food for the day.

“a holy Sabbath.” This is the first time in the Bible that the word “Sabbath” is used, and so God has to describe it as a “day of rest.” Although the REV capitalizes “Sabbath,” it is possible that the better choice would be to simply have “sabbath” in this verse because the formal weekly “Sabbath” was just being put in place. This is the first time a regular weekly rest was mentioned, then in the Ten Commandments, “the Sabbath” became clarified and set forth as part of the Old Covenant and Mosaic Law.

[For more on the Sabbath, see commentary on Exodus 20:10.]