And the LORD went before them by day in a pillar of a cloud, to lead them the way; and by night in a pillar of fire, to give them light; to go by day and night: The Lord went before them - That by the Lord here is meant the Lord Jesus, we have the authority of St. Paul to believe, 1 Corinthians 10:9 : it was he whose Spirit they tempted in the wilderness, for it was he who led them through the desert to the promised rest.
Pillar of a cloud - This pillar or column, which appeared as a cloud by day, and a fire by night, was the symbol of the Divine presence. This was the Shechinah or Divine dwelling place, and was the continual proof of the presence and protection of God. It was necessary that they should have a guide to direct them through the wilderness, even had they taken the most direct road; and how much more so when they took a circuitous route not usually traveled, and of which they knew nothing but just as the luminous pillar pointed out the way! Besides, it is very likely that even Moses himself did not know the route which God had determined on, nor the places of encampment, till the pillar that went before them became stationary, and thus pointed out, not only the road, but the different places of rest. Whether there was more than one pillar is not clearly determined by the text. If there was but one it certainly assumed three different appearances, for the performance of Three very important offices. 1. In the day-time, for the purpose of pointing out the way, a column or pillar of a cloud was all that was requisite. 2. At night, to prevent that confusion which must otherwise have taken place, the pillar of cloud became a pillar of fire, not to direct their journeyings, for they seldom traveled by night, but to give light to every part of the Israelitish camp. 3. In such a scorching, barren, thirsty desert, something farther was necessary than a light and a guide. Women, children, and comparatively infirm persons, exposed to the rays of such a burning sun, must have been destroyed if without a covering; hence we find that a cloud overshadowed them: and from what St. Paul observes, 1 Corinthians 10:1, 1 Corinthians 10:2, we are led to conclude that this covering cloud was composed of aqueous particles for the cooling of the atmosphere and refreshment of themselves and their cattle; for he represents the whole camp as being sprinkled or immersed in the humidity of its vapours, and expressly calls it a being under the cloud and being baptized in the cloud. To the circumstance of the cloud covering them, there are several references in Scripture. Thus: He spread a Cloud for their Covering; Psalms 105:39. And the Lord will create upon every dwelling place of Mount Zion, and upon her assemblies, A Cloud and Smoke By Day, and the shining of a Flaming Fire by night; for upon all the glory shall be a Defence, (or Covering), Isaiah 4:5; which words contain the most manifest allusion to the threefold office of the cloud in the wilderness. See Numbers 9:16-18, etc.