Charles Ellicott Commentary Numbers 11:31

"And there went forth a wind from Jehovah, and brought quails from the sea, and let them fall by the camp, about a day`s journey on this side, and a day`s journey on the other side, round about the camp, and about two cubits above the face of the earth." — Numbers 11:31 (ASV)

And there went forth a wind. In Psalms 78:26 we read: He caused an east wind to blow in the heaven: and by his power he brought in the south wind. A south-east wind would bring the quails from the neighbourhood of the Red Sea, where they abound.

And let them fall. Better, and scattered them (or, spread them out). Compare 1 Samuel 30:16: They were spread abroad upon all the earth, or, over all the ground.

Round about. See Note on Numbers 11:24.

As it were two cubits high upon the face of the earth. Or, about two cubits over (or, above) the ground. Had the quails lain upon the earth in a heap for any considerable time, life could only have been preserved by miraculous interference with the ordinary laws of nature, and the Israelites were not allowed to eat anything that had died of itself. Quails commonly fly low, and when weary from a long flight, they might fly only about breast-high.

On the other hand, the more obvious interpretation of the words is that the quails were spread over the ground, and in some places covered it to the height of two cubits. They were probably taken and killed immediately on their descent, as the following verse seems to indicate, and then spread out, dried, and hardened in the sun. Some think that the word which is here rendered quails denotes cranes.