21, 22. the Lord went before them—by a visible token of His presence, the Shekinah, in a majestic cloud (Ps 78:14; Ne 9:12; 1Co 10:1), called "the angel of God" (Ex 14:19; 23:20-23; Ps 99:6, 7; Isa 63:8, 9).

     15. the cloud covered the tabernacle—The inspired historian here enters on an entirely new subject, which might properly have formed a separate chapter, beginning at this verse and ending at Nu 10:29 [CALMET]. The cloud was a visible token of God's special presence and guardian care of the Israelites (Ex 14:20; Ps 105:39). It was easily distinguishable from all other clouds by its peculiar form and its fixed position; for from the day of the completion of the tabernacle it rested by day as a dark, by night as a fiery, column on that part of the sanctuary which contained the ark of the testimony (Le 16:2).