Verse 2
Exodus 13:2. Sanctify — That is, command all the people to sanctify; unto me — To my use and service, in a manner I shall hereafter explain; all the firstborn — That are males, as the command is limited, Exodus 13:12; whatsoever openeth the womb — That is, every child which is the firstborn of his mother: so that if a man had many wives, either together or successively, his first child by every one of these was a firstborn, and, if a male, was claimed by the Lord. But if a female came first, and afterward a male, that male was not devoted to God, because it was not the firstborn. Hence the parents were not to look upon themselves as having an interest in their firstborn, if males, till they had first solemnly presented them to God, and received them back from him again. It is mine — By special right and title, as being by singular favour preserved from the common destruction. The firstborn of man, if males, were claimed for the sacred ministrations of the priestly office. But after the Jewish commonwealth was formed, the Levites were chosen to officiate in their stead, Numbers 3:12; and the firstborn were to be redeemed at a certain rate, which was part of the priest’s maintenance, Numbers 18:15-16. And of beast — Which was to be offered to God, if a male: only an ass was to be redeemed.

Verse 5
Exodus 13:5. When the Lord shall bring you into the land, thou shalt keep this service — Until then they were not obliged to keep the passover, without a particular command from God. There shall no leavened bread be seen in all thy quarters — Accordingly the Jews’ usage was, before the feast of the passover, to cast all the leavened bread out of their houses; either they burned it, or buried it, or broke it small, and threw it into the wind; they searched diligently with lighted candles in all the corners of their houses, lest any leaven should remain. The strictness enjoined in this matter was designed, 1st, To make the feast the more solemn, and consequently the more taken notice of by the children, who would ask, Why is so much ado made? 2d, To teach us how solicitous we should be to put away from us all sin.

Verse 8
Exodus 13:8. Thou shalt show thy son — When you shall be come into the land of Canaan, you shall instruct your children in the meaning of your killing the lamb, and abstaining from leaven, that so you and they may be excited to gratitude to God for his goodness. This was evidently the design of the institution.

Verse 9
Exodus 13:9. Upon thy hand, between thine eyes — Proverbial expressions, denoting that these things were never to be out of their minds. The Jews, however, understood this literally, and hence the use of phylacteries among them, pieces of parchment inscribed with sentences of their law, which they bound upon their left hand, and placed upon their foreheads between their eyes.

Verse 12
Exodus 13:12. Every firstling of a beast shall be the Lord’s — That is, every firstling male of a clean beast, as of the cow, sheep, or goat kind, was to be offered in sacrifice; and the blood being sprinkled, and the fat burned on the altar, the flesh of them was to be given to the priests, Numbers 18:17-18.

Verse 13
Exodus 13:13. Every firstling of an ass thou shalt redeem with a lamb — Or kid, Exodus 12:3; and the same is to be understood of all unclean beasts in general, see Numbers 18:15. The ass seems to be particularly mentioned, because those animals were more numerous among them than other beasts of burden. If a man had not a lamb, he was to give the price of one. This lamb was to be given to the Lord; that is, to his priest.

Verse 16
Exodus 13:16. For frontlets between thine eyes — As conspicuous as any thing fixed to thy forehead, or between thine eyes. That is, they were constantly to retain such a sense of their deliverance as if they had it before their eyes.

Verse 18
Exodus 13:18. There were various reasons why God led them through the way of the wilderness of the Red sea. The Egyptians were to be drowned in the Red sea, the Israelites were to be humbled and proved in the wilderness, Deuteronomy 8:2. God had given it to Moses for a sign, Exodus 3:12, Ye shall serve God in this mountain. They had again and again told Pharaoh that they must go three days’ journey into the wilderness to do sacrifice, and therefore it was requisite they should march that way, else they had justly been exclaimed against as dissemblers. Before they entered the lists with their enemies, matters must be settled between them and their God; laws must be given, ordinances instituted, covenants sealed; and for the doing of this it was necessary they should retire into the solitudes of a wilderness, the only closet for such a crowd; the high road would be no proper place for these transactions. The reason why God did not lead them the nearest way, which would have brought them in a few days to the land of the Philistines, was because they were not yet fit for war, much less for war with the Philistines. Their spirits were broken with slavery; the Philistines were formidable enemies; it was convenient they should begin with the Amalekites, and be prepared for the wars of Canaan, by experiencing the difficulties of the wilderness. God is said to bring Israel out of Egypt, as the eagle brings up her young ones, Deuteronomy 32:11, teaching them by degrees to fly. They went up harnessed — The original word for harnessed here is variously rendered: it comes from a root which signifies five, hence some render it five in a rank. The same word is rendered prepared for war, Joshua 1:14; Joshua 4:12-13. Targum, girded, harnessed. Vulg. armati, armed. So the Seventy, ευζωνοι equipped, διεσκυασμενοι prepared, furnished: thus in Joshua; but in this place of Exodus the Seventy render the word πεντη γενεα, the fifth generation, and translate the passage, In the fifth generation, the children of Israel went up out of the land of Egypt.

Verse 21
Exodus 13:21. And the Lord went before them in a pillar — In the first two 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 previous 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 as 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 some times of the year was extreme, and it gave them light by night when they had occasion for it.

Verse 22
Exodus 13:22. He took not away the pillar of the cloud — No, not when they seemed to have less occasion for it: it never left them until it brought them to the borders of Canaan. It was a cloud which the wind could not scatter. There was something spiritual in this pillar of cloud and fire. 1st, The children of Israel were baptized unto Moses in this cloud, 1 Corinthians 10:2. By coming under this cloud they signified their putting themselves under the conduct and command of Moses. Protection draws allegiance; this cloud was the badge of God’s protection, and so became the bond of their allegiance. Thus they were initiated, and admitted under that government, now when they were entering upon the wilderness. 2d, And it signifies the special conduct and protection which the church of Christ is under in this world.