(21) The Lord went before them.--In Exodus 13:17-18, the writer has declared that "God led the people;" he now explains how. from Succoth certainly, probably from Rameses, He moved in front of the host in the form of a pillar, which had the appearance of smoke by day and of fire by night. The Israelites marched, it is implied, some part of each day and some part of each night, which would be in accordance with modern practice, and is an arrangement introduced to get the march accomplished before the sun attains his full power. The pillar was at once a signal and a guide. When it moved, the people moved; when it stopped, they encamped (Exodus 40:36-38); where it went, they followed. It bore some resemblance to the fire and smoke signals which generals used when at the head of their armies (Lepsius, Denkmaler, vol. ii., pl. 150, 2; Papyr. Anastas, 1; Q. Curt, Vit. Alex. v. 2, &c), and indicated that God had constituted Himself the generalissimo of the host; but it was altogether of a miraculous and abnormal character.

To go by day and night.--The night journeys of the people are mentioned again in Numbers 9:21.

Verses 21, 22. - THE PILLAR OF THE CLOUD AND OF FIRE. Having stated, in verse 17, that "God led the Israelites," and determined their route for them, the writer here proceeds to explain how this leading was accomplished. With extreme simplicity and directness he states, that the conduct was effected by means of an appearance, which in the daytime was like a column or pillar of smoke ascending from earth to heaven, and in the night was like a pillar of fire. He considers the presence of God to have been in the pillar, which moved in front of the host, and showed them the way that they were to go. When it halted, they halted when it advanced, they advanced. Their journeys being made as much in the night-time as in the day, on account of the intense heat, the pillar took in the night the appearance of a column of fire, so as to be equally visible as by day. All attempts to give a rational explanation of the phenomenon are misplaced, since the writer, from whom alone we derive our information on the subject, clearly regarded it as miraculous; and both here and elsewhere (Exodus 14:19, 20, 24; Exodus 33:9; Numbers 12:5; Numbers 14:11) speaks of it as a form under which God was pleased to show himself. There is little doubt that fire and smoke signals were already used by commanders of armies for much the same purpose as that which God now accomplished in this way. The Egyptian documents of the period contain indications of the usage; and it is found among the Arabians, the Greeks, and the Persians. (See especially Q. Curt. Vit. Alex. 5:2; "Perticam, quae undique conspici posset, supra praetorium statuit, ex qua signum eminebat pariter omnibus conspicuum: observabatur ignis noctu, fiunus interdin.") The miracle was thus, in a certain sense, founded upon an existing custom, with the difference that God here gave the signals miraculously, which were wont to be given in a natural way by the human leaders of armies. He thus constituted himself the general of the host. Verse 21. - The Lord went before them. From Succoth at any rate; perhaps even on the journey from Rameses to Succoth. In a pillar of cloud. The pillar was seen - the presence of Jehovah, though unseen, was believed to be in it, and to move it. To go by day and night. Or, "so that they might march both by day and by night." Night marches are generally preferred by Orientals on account of the great heat of the days. The night-marches of the Israelites are again mentioned in Numbers 9:21.

13:21,22 The Lord went before them in a pillar, or appearance of the Divine Majesty. Christ was with the church in the wilderness, 1Co 10:9. Those whom God brings into a wilderness, he will not leave nor lose there, but will take care to lead them through it. It was great satisfaction to Moses and the pious Israelites, to be sure that they were under Divine guidance. Those 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 sure that the Lord goes before them, though they cannot see it with their eyes: we must now live by faith. When Israel marched, this pillar went before, and pointed out the place of encampment, as Divine Wisdom saw fit. It sheltered by day from the heat, and gave light by night. The Bible is a light to our feet, a lantern to our paths, with which the Saviour's love has provided us. It testifies of Christ. It is to us like the pillar to the Israelites. Listen to that voice which cries, I am the Light of the world; he that followeth me shall not walk in darkness, but shall have the Light of life, Joh 8:12. Jesus Christ alone, as shown in the Bible, and as the Holy Spirit, in answer to prayer, recommends him to the soul, is the Way, the Truth, and the Life, Joh 14:6.And the Lord went before them,.... Who is called the Angel of the Lord, Exodus 14:19, not a created but the uncreated Angel, the Angel of Jehovah's presence, in whom his name, nature, and perfections were, even the Word and Son of God, the Lord Christ, see 1 Corinthians 10:9 who went before the armies of Israel, as their King, Leader, and Commander:

by day in a pillar of a cloud, to lead them the way; through the Red sea, and the wilderness, at the edge of which they now were, which was untrodden, and trackless, and the way through it very difficult to find; and being a sandy desert, as soon as a path was made, it was immediately covered with sand, and to be seen no more: this cloud was not an ordinary one, but extraordinary, supernatural, and miraculous; in the superior part of it, it was in the form of a pillar, rising upwards towards heaven; in the lower part of it, it was more spread, and covered the camp of Israel; for, besides the use of it to show the way through a trackless wilderness, it was a shelter and protection from the scorching heat of the sun in a sandy desert, where there was scarce anything to screen them from it, to which the allusion is in Isaiah 4:5 this cloud was an emblem of Christ, who has sometimes appeared clothed with a cloud, Revelation 10:1 of the obscurity of his human nature, of the fulness of grace in him, and being in the form of a pillar, of his uprightness, firmness, stability, and visibility in it; and of the use and benefit he is to his people, partly to show them the way in which they should go, by his Spirit and word, and lead them in it by his own example, whom it becomes them to follow, he being a wise, safe, and constant guide; and partly to shelter and protect them from the heat of a fiery law, from the flaming sword of justice, from the wrath of God, from the fiery darts of Satan, and from the furious persecution of wicked men, sometimes compared to the violent heat of the sun, Sol 1:6.

and by night in a pillar of fire, to give them light; whenever they travelled by night, as they sometimes did, and in those hot countries it was very agreeable; and this pillar of fire gave them light when the moon shone not, and was a direction to them which way to go: sometimes it is night with the people of God, a night of darkness and desertion, of drowsiness, sleepiness, and carnal security, or of affliction and distress: Christ is the light and comfort of his people, and by his Spirit and word illuminates, guides, and directs them what to do, and where and how to walk:

to go by day or night; to direct them in their journey, whether by night or day: this was but one pillar, though Aben Ezra thinks they were two; but it may be observed they are mentioned as one, and that the pillar of cloud in the night was a cloud of darkness to the Egyptians, and gave light to the Israelites, Exodus 14:19, see also Numbers 9:21 and it is easy to observe that what appears as a cloud or smoke in the daytime, looks like fire in the night: so when Alexander's army was on the march, as a signal,"fire was observed in the night, and smoke by day,''as says the historian (x): nor can, this account of Moses seem incredible to the Heathens themselves, as Clemens of Alexandria observes (y), since they relate a story somewhat similar to this, which they profess to believe; as, that when Thrasybulus brought the exile Grecians from Phyle, and willing to do it secretly, a pillar was his guide, and as he passed in the night through untrodden paths, when the moon shone not, and it was a dark winter night, a light was seen going before him, which brought them safe to Mynichia, and then left them: indeed this was not so extraordinary and miraculous, if true, as this pillar, as Bishop Patrick observes, because it was but for a night, whereas this continued all the forty years in the wilderness, until the Israelites came to Canaan's land, as follows: the Arabic geographer (z) speaks of exhalations arising out of caves at the sides of mountains, which in the daytime looked like smoke, and in the night time like fire.

(x) Curtius, l. 5. c. 2.((y) Strom. l. 1. p. 348. (z) Climat. 3. par. 8.