At the command of the LORD the people of Israel set out, and at the command of the LORD they camped. As long as the cloud rested over the tabernacle, they remained in camp.
18. At the commandment of the Lord. “At the mouth of the Lord.” — Lat. The mouth is here used by metonymy for the speech; nor does there appear to me to be so much harshness in the Hebraism, but that it may be appropriately retained. But it is asked whether God actually spoke or not; for the word mouth is often repeated.
We have here the history of the cloud; not a natural history: who knows the balancings of the clouds? but a divine history of a cloud that was appointed to be the visible sign and symbol of God's presence with Israel. I.
Commenting on Numbers 9:15-23
And when the cloud tarried long upon the tabernacle many days,.... Or years, for days are sometimes put for years, and in some places the cloud tarried several years; or however, if it stayed but a month or a year in any place, as in Num 9:22, then the children of Israel kept the charge of the Lord, and journeyed not; they not only kept...