In the latter years thou shalt come - This was fulfilled about four hundred years after. - Martin. The expedition of Cambyses against Egypt was about twelve years after the return of the Jews from Babylon. - Calmet.
As Gog was drawn on to his attack upon Israel in order to his ultimate ruin, therefore his preparations were the first step in his visitation from the Almighty.
After many days - For “many days.” Many a long day shall the hand of God be upon thee, drawing thee on to thy ruin, and in the latter days shalt thou come.
The land - literally, a “land” once laid waste by the sword, but now delivered from it, whose inhabitants once scattered have been gathered together from out of many peoples.
Always - Rather, a long time. The mountains were at the time of Gog‘s advance again cultivated and populous.
And they shall dwell - Rather, and they dwell. It is a description of the actual condition at the time of Gog‘s invasion (compare Judges 18:7). Such was the condition of the restored Jews in their prosperous days, after which came invasion. Such shall be the condition of the Church previous to the final conflict between good and evil.