Albert Barnes Commentary Ezekiel 37:9

"Then said he unto me, Prophesy unto the wind, prophesy, son of man, and say to the wind, Thus saith the Lord Jehovah: Come from the four winds, O breath, and breathe upon these slain, that they may live." — Ezekiel 37:9 (ASV)

The wind - Rather, as noted in the margin and as in Ezekiel 37:5. The bones are the bones of the "slain," because the scene was one which was likely to occur during the Chaldaean invasion, and the fact of violent death reminded the prophet of the miserable condition of the people.