Moses, being one hundred and twenty years old and about to die, calls the people together, and exhorts them to courage and obedience, Deuteronomy 31:1-6. Delivers a charge to Joshua, Deuteronomy 31:7, Deuteronomy 31:8. Delivers the law which he hod written to the priests, with a solemn charge that they should read it every seventh year, publicly to all the people, Deuteronomy 31:9-13. The Lord calls Moses and Joshua to the tabernacle, Deuteronomy 31:14. He appears to them, informs Moses of his approaching death, and delivers to him a prophetical and historical song, or poem, which he is to leave with Israel, for their instruction and reproof, Deuteronomy 31:15-21. Moses writes the song the same day, and teaches it to the Israelites, Deuteronomy 31:22; gives Joshua a charge, Deuteronomy 31:23; finishes writing the book of the law, Deuteronomy 31:24. Commands the Levites to lay it up in the side of the ark, Deuteronomy 31:25, Deuteronomy 31:26. Predicts their rebellions, Deuteronomy 31:27. Orders the elders to be gathered together, and shows them what evils would befall the people in the latter days, Deuteronomy 31:28, Deuteronomy 31:29, and repeats the song to them, Deuteronomy 31:30.

I am a hundred and twenty years old - The life of Moses, the great prophet of God and lawgiver of the Jews, was exactly the same in length as the time Noah employed in preaching righteousness to the antediluvian world. These one hundred and twenty years were divided into three remarkable periods: forty years he lived in Egypt, in Pharaoh's court, acquiring all the learning and wisdom of the Egyptians; (see Acts 7:20, Acts 7:23); forty years he sojourned in the land of Midian in a state of preparation for his great and important mission; (Acts 7:29, Acts 7:30); and forty years he guided, led, and governed the Israelites under the express direction and authority of God: in all, one hundred and twenty years.

Joshua, he shall go over before thee - See on Numbers 27:17 (note), etc.

Be strong - חזקו chizku, the same word that is used Exodus 4:21 (note), Exodus 9:15 (note), for hardening Pharaoh's heart. See the notes there. The Septuagint, in this and the following verse, have, Ανδριζου και ισχυε, Play the man, and be strong; and from this St. Paul seems to have borrowed his ideas, 1 Corinthians 16:13 : Στηκετε εν τῃ πιστει· ανδριζεσθε, κρατιουσθε: Stand firm in the faith; play the man - act like heroes; be vigorous.

The Lord - doth go before thee - To prepare thy way, and to direct thee.

He will be with thee - Accompany thee in all thy journeys, and assist thee in all thy enterprises.

He will not fail thee - Thy expectation, however strong and extensive, shall never be disappointed: thou canst not expect too much from him.

Neither forsake thee - He knows that without him thou canst do nothing, and therefore he will continue with thee, and in such a manner too that the excellence of the power shall appear to be of him, and not of man.

Moses wrote this law - Not the whole Pentateuch, but either the discourses and precepts mentioned in the preceding chapters, or the book of Deuteronomy, which is most likely.

Some of the rabbins have pretended that Moses wrote thirteen copies of the whole Pentateuch; that he gave one to each of the twelve tribes, and the thirteenth was laid up by the ark. This opinion deserves little credit. Some think that he wrote two copies, one of which he gave to the priests and Levites for general use, according to what is said in this verse, the other to be laid up beside the ark as a standard copy for reference, and to be a witness against the people should they break it or become idolatrous. This second copy is supposed to be intended Deuteronomy 31:26. As the law was properly a covenant or contract between God and the people, it is natural to suppose there were two copies of it, that each of the contracting parties might have one: therefore one was laid up beside the ark, this was the Lord's copy; another was given to the priests and Levites, this was the people's copy.

At the end of every seven years - thou shalt read this law - Every seventh year was a year of release, Deuteronomy 15:1, at which time the people's minds, being under a peculiar degree of solemnity, were better disposed to hear and profit by the words of God. I suppose on this ground also that the whole book of Deuteronomy is meant, as it alone contains an epitome of the whole Pentateuch. And in this way some of the chief Jewish rabbins understand this place.

It is strange that this commandment, relative to a public reading of the law every seven years, should have been rarely attended to. It does not appear that from the time mentioned Joshua 8:30, at which time this public reading first took place, till the reign of Jehoshaphat 2 Chronicles 17:7, there was any public seventh year reading - a period of 530 years. The next seventh year reading was not till the eighteenth year of the reign of Josiah, 2 Chronicles 34:30, a space of two hundred and eighty-two years. Nor do we find any other publicly mentioned from this time till the return from the Babylonish captivity, Nehemiah 8:2. Nor is there any other on record from that time to the destruction of Jerusalem. See Dodd.

Behold, thou shalt sleep with thy fathers - שכב shocheb, thou shalt lie down; it signifies to rest, take rest in sleep, and, metaphorically, to die. Much stress cannot be safely laid on this expression to prove the immortality of the soul, or that the people in the time of Moses had a distinct notion of its separate existence. It was, however, understood in this sense by Jonathan ben Uzziel, who in his Targum paraphrases the word thus: "Thou shalt lie down in the dust with thy fathers; and thy soul (נשמתך nishmethach) shall be laid up in the treasury of the life to come with thy fathers."

I will surely hide my face - Withdraw my approbation and my protection. This is a general meaning of the word in Scripture.

Write ye this song - The song which follows in the next chapter. Things which were of great importance and of common concern were, among the ancients, put into verse, as this was found the best method of keeping them in remembrance, especially in those times when writing was little practiced. Even prose was sometimes sung. The history of Herodotus was divided into Nine books, and each inscribed with the name of one of the Nine Muses, because these books were anciently sung. Homer is reported to have sung his poems through different Greek cities. Aristotle observes that anciently the people sung their laws. And Cicero observes that it was a custom among the ancient Romans to sing the praises of their heroes at the public festivals. This was the case among the northern inhabitants of Europe, particularly in Ireland and Scotland; hence the Gaelic poetry of Ossian and others. See Dodd; and see the note on Exodus 15:1, where the subject is largely treated.

This song shall testify against them - Because in it their general defection is predicted, but in such a way as to show them how to avoid the evil; and if they did not avoid the evil, and the threatened punishment should come upon them, then the song should testify against them, by showing that they had been sufficiently warned, and might have lived to God, and so escaped those disasters.

Take this book of the law - The standard copy to which all transcripts must ultimately refer: another copy was put into the bands of the priests. See the note on Deuteronomy 31:9.

While I am yet alive - ye have been rebellious - Such was the disposition of this people to act contrary to moral goodness that Moses felt himself justified in inferring what would take place from what had already happened.

1. Never was a people more fully and faithfully warned, and from this very circumstance we may see that they were under no fatal constraining necessity to commit sin against God; they might have avoided it, but they would not. God was present to help them, till by their repeated provocations they forced him to depart: wrath therefore came upon them to the uttermost because they sinned when they might have lived to the glory of God. Those who abuse God's grace shall not only have that grace taken away from them, but shall be punished for the abuse of it, as well as for the transgression. Every sin is double, and must have a twofold punishment; for 1. Grace is resisted; 2. Transgression is committed; and God will visit for both.

2. How astonishing it is that, with such examples of God's justice before their eyes, the Jews should be so little affected; and that the Gentiles, who have received the Gospel of God, should act as if God would no more punish transgression, or that he must be so partial to them as to pass by iniquities for which the hand of his justice still continues heavy upon the descendants of Jacob! Let them take heed, for if God spared not the natural branches, he will not spare them. If they sin after the manner of the Jews, they may expect to be partakers with them in their punishments. What God does to nations he will do to individuals who reject his mercy, or trample under foot his grace; the soul that sinneth, and returns not to God by repentance and faith, shall die. This is a decree of God that shall never be reversed, and every day bears witness how strictly he keeps it in view.

3. The ode composed by Moses for this occasion was probably set to some lively and affecting air, and sung by the people. It would be much easier to keep such a song in remembrance, than an equal quantity of prose. The whole would have the additional circumstances of cadence and tune to cause it to be often repeated; and thus insure its being kept in memory. Poetry, though often, nay, generally abused, is nevertheless a gift from God, and may be employed with the best effect in his service. A very considerable part of the Old Testament is written in poetry; particularly the whole book of Psalms, great part of the prophet Isaiah, the Lamentations, and much of the minor prophets. Those who speak against poetic compositions in the service of God, speak against what they do not understand. All that a man hath should be consecrated to his Maker, and employed in his service; not only the energy of his heart and mind, the physical force of his body, but also the musical tones and modulations of his voice.