they kept: Num 9:19, Gen 26:5, Jos 22:3, Eze 44:8, Zec 3:7, Some of the Levites may have been appointed to watch the moving of the pillar, and to give timely notice to the camp of its beginning to stir; and this is called "keeping the charge of the Lord." It is uncomfortable staying when God is departed, but very safe and pleasant going, when we see God go before us, and resting where he appoints us to rest. Reciprocal: Num 10:13 - General