John Calvin Commentary Exodus 16:1

"And they took their journey from Elim, and all the congregation of the children of Israel came unto the wilderness of Sin, which is between Elim and Sinai, on the fifteenth day of the second month after their departing out of the land of Egypt." — Exodus 16:1 (ASV)

And they took their journey. Moses relates that when, after a month, the people came to the wilderness of Sin near Mount Sinai, and when their provision failed, they rebelled against God and Moses, and manna, a new and unusual kind of food, was given to them from heaven.

It is uncertain with what foods they were sustained in the meantime. Some conjecture that they brought sufficient flour from Egypt for their supply. However, to me it seems probable that other kinds of food were used in addition.

For the barrenness of the country through which they passed was not so great as to prevent it from producing at least fruits and herbs. Besides, from the battle in which, as will soon be related, they conquered the Amalekites, we may readily suppose that they were not far from a habitable territory.

But when they were carried away farther into the desert, all their provision began to fail because they had no more commerce with the inhabitants. Therefore, their sedition increased, because hunger pressed upon them more than usual.

For, although we will later be able to gather from the context that there was some previous disturbance in the camp, famine—which now began to affect them more because the barrenness on all sides in these uncultivated and miserable regions alarmed them—still gave strength to their murmurs and impatience.