For seven months the house of Israel will be burying them in order to cleanse the land.
God speaks of this victory as already done, though the fulfillment lies ahead, because it is as certain as if accomplished. The routed army leaves behind such mountains of weapons that Israel will burn them for fuel seven years instead of cutting wood from the forests, turning the instruments of war into the ordinary means of warming their homes.
AI summary
Commenting on Ezekiel 39:8-22
And seven months shall the house of Israel be burying of them,.... So long time will the burial of Gog's army take up, because of the multitude of it, and by reason their bones will be scattered here and there; which will require time to gather them together, and bring them to one place: the reason of the burial of them will be, partly out...
And seven months shall the house of Israel be in burying them, that they may cleanse the land. (h) Meaning a long time.