פּירוש אויף יהושע 5:12

“The manna ceased” [5:12]. The manna ceased to be given to Israel on the seventeenth day of Nisan. They had gladly eaten manna, but when the manna ceased they had to eat the grain of the land of Israel.⁷Radak, Joshua, 5:12.

The Tosefta writes. The Israelites ate the manna for forty years because of the merit of Moses and even though Moses had died, they still ate the manna because of his merit. Moses died on the seventh day of the month of Adar and the manna fell on that day. The Israelites collected the same manna and ate from it for thirtynine days, until the sixteenth day of Nisan. The offered the Omer, a baked cake made of new barley. This was called the Omer sacrifice and they were not supposed to eat the new grain. They first had to offer the Omer.⁸Tosefta Sotah, 11.2; Yalkut Shimoni, Joshua, Remez, 15.

No longer did the Bnei Yisroel have manna. Therefore they ate of the grain of the land. If they would have had manna they would not have eaten of the grain, for the manna was agreeable to them. There is a parable for this: One says to a child, “Why are you eating barley bread?” “Because I have no wheat bread.” That is why it is said, ‘no longer did etc.’