Exodus 13:21

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; Psalm 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.

Pillar of cloud - The Lord Himself did for the Israelites by preternatural means that which armies were obliged to do for themselves by natural agents. The Persians and Greeks used fire and smoke as signals in their marches, and in a well-known papyrus, the commander of an Egyptian expedition is called "A flame in the darkness at the head of his soldiers." By this sign then of the pillar of cloud, the Lord showed Himself as their leader and general Exodus 15:3, Exodus 15:6.

13:21 And the Lord went before them in a pillar — In the two first stages, it was enough that God directed Moses whither to march; he knew the country, and the road; but now they are come to the edge of the wilderness, they would have occasion for a guide, and a very good guide they had, infinitely wise, kind, and faithful, the Lord went up before them; The Shechinah or appearance of the divine Majesty, which was a precious manifestation of the eternal Word, who in the fulness of time was to be made flesh, and dwell among us. Christ was with the church in the wilderness, 1 Corinthians 10:9. What a satisfaction to Moses and the pious Israelites, to be sure that they were under a divine conduct? They need not fear missing their way who were thus led, nor being lost who were thus directed; they need not fear being benighted, who were thus illuminated, nor being robbed, who were thus protected. And they who make the glory of God their end, and the word of God their rule, the spirit of God the guide of their affections, and the providence of God the guide of their affairs, may be confident that the Lord goes before them, as truly is he went before Israel in the wilderness, though not so sensibly. They had sensible effects of God's going before them in this pillar. For, It led them the way in that vast howling wilderness, in which there was no road, no track, no way-marks through which they had no guides. When they marched, this pillar went before them, at the rate that they could follow, and appointed the place of their encampment, as infinite Wisdom saw fit; which eased them from care, and secured them from danger, both in moving, and in resting. It sheltered them from the heat by day, which at sometimes of the year was extreme: And it gave them light by night when they had occasion for it.