The Pulpit Commentary - Exodus 40:38
The cloud … was upon the tabernacle by day and fire was on. it by night . Compare Exodus 13:21 , Exodus 13:22 ; and Exodus 14:20 , Exodus 14:24 ; Numbers 9:15 , Numbers 9:16 . The cloud had two aspects—one obscure, the other radiant. It was a dark column by day—a pillar of fire by night. Thus it was always visible. read more
The Pulpit Commentary - Exodus 40:36-38
And when — i.e. "whensoever." The last three verses describe the manner in which the cloud henceforth served the Israelites as guide—not only directing their course, but determining when they were to move, and how long they were to rest at each encampment. For a further account of the same, see Numbers 9:15-23 . read more