It was only ever given
a day at a time.Exodus 16:4 (NIV)

“The people are to go out each day and gather enough for that day.” — Exodus 16:4 (NIV)

They had asked for food, and they got it, and then they found out the terms.

It came in the morning and it would not last the night. Read on a few verses and some of them tried it anyway — gathered extra, put it by, and found it spoiled by morning. The one exception was the day before the sabbath, when two days' worth was given and kept, because they were not to be working. Otherwise: today's, and nothing in reserve. Forty years of that, the chapter says at the end. Not one week's certainty in the whole of it.

It is not the arrangement most of us would choose. We would rather have the year in hand — the money in place, the letter that settles it, the answer about the job — and walk into it knowing how it comes out. What they were given was breakfast.

Whatever you wanted settled tonight will most likely not be settled by morning. What you will have is the morning, and enough for it. That has been the arrangement a long time, and people have come a very long way on it.