Let not his men be few - literally, "a number," i. e., "a small number," such as could be easily counted (compare Genesis 34:30 note). While the verse promises that the tribe shall endure and prosper, yet it is so worded as to carry with it a warning. The Reubenites, occupied with their herds and flocks, appear, soon after the days of Joshua, to have lost their early energy, until in later times its numbers, even when counted with the Gadites and the half of Manasseh, were fewer than that of the Reubenites alone at the census of Numbers. 1 (Compare 1-Chronicles 5:18 with Numbers 1:20.) No judge, prophet, or national hero arose out of this tribe.
The tribe of Simeon, which would according to the order of birth come next, is not here named. This omission is explained by reference to the words of Jacob concerning Simeon Genesis 49:7. This tribe with Levi was to he "scattered in Israel." The fulfillment of this prediction was in the case of Levi so ordered as to carry with it honor and blessing; but no such reversal of punishment was granted to Simeon. Rather had this latter tribe added new sins to those which Jacob denounced (compare Numbers 26:5 note). Accordingly, though very numerous at the Exodus, it had surprisingly diminished before the death of Moses (compare Numbers 1:22-23 with Numbers 26:12-14); and eventually it found territory adequate for its wants within the limits of another tribe, Judah. Compare Joshua 19:2-9.

Let Reuben live, and not die - Though his life and his blessings have been forfeited by his transgression with his father's concubine, Genesis 49:3, Genesis 49:4; and in his rebellion with Korah, Numbers 16:1-3, etc., let him not become extinct as a tribe in Israel. "It is very usual," says Mr. Ainsworth, "in the Scripture, to set down things of importance and earnestness, by affirmation of the one part, and denial of the other; Isaiah 38:1 : Thou shalt die, and not live; Numbers 4:19 : That they may live, and not die; Psalm 118:17 : I shall not die, but live; Genesis 43:8 : That we may live, and not die; Jeremiah 20:14 : Cursed be the day - let not that day be blessed; 1-John 2:4 : He is a liar, and the truth is not in him; 1-John 2:27 : Is truth, and no lie; John 1:20 : He confessed, and denied not; 1-Samuel 1:11 : Remember me, and not forget thy handmaid; Deuteronomy 9:7 : Remember, forget not; Deuteronomy 32:6 : O foolish people, and unwise. In all these places it is evident that there is a peculiar emphasis in this form of expression, as if he had said, Let him not only not die, but let him live in great and increasing peace and prosperity. Do not only not forget me, but keep me continually in remembrance. He denied not, but confessed Fully and Particularly. O foolish people - silly and stupid, and unwise - destitute of all true wisdom."
And let not his men be few - It is possible that this clause belongs to Simeon. In the Alexandrian copy of the Septuagint the clause stands thus: Και Συμεων εστω πολυς εν αριτμῳ, and let Simeon be very numerous, but none of the other versions insert the word. As the negative particle is not in the Hebrew, but is supplied in our translation, and the word Simeon is found in one of the most ancient and most authentic copies of the Septuagint version; and as Simeon is nowhere else mentioned here, if not implied in this place, probably the clause anciently stood: Let Reuben live, and not die; but let the men of Simeon be few. That this tribe was small when compared with the rest, and with what it once was, is evident enough from the first census, taken after they came out of Egypt, and that in the plains of Moab nearly forty years after. In the first, Simeon was 59,300; in the last, 22,200, a decrease of 37,100 men!

Let (f) Reuben live, and not die; and let [not] his men be few.
(f) Reuben will be one of the tribes of God's people, though for his sin his honour is diminished, and his family but small.

Let Reuben live, and not die,.... As a tribe, continue and not be extinct, though they should not excel, because of the sin of their progenitor; and it may have a special regard to the preservation of them, of their families on the other side Jordan, while they passed over it with their brethren into Canaan, and of them in that expedition to help the other tribes in the conquest of the country and the settlement of them in it; which Jacob by a spirit of prophecy foresaw, and in a prayer of faith petitioned for their safety: all the three Targums refer the words to a future state, as a wish for them, that they might live and enjoy an eternal life, and not die the death of the wicked in the world to come; and which they call the second death, and from whom the Apostle John seems to have borrowed the phrase, Revelation 2:11 Revelation 20:6; Reuben signifies, "see the Son"; and all that see the Son of God in a spiritual manner, and believe in him with a true faith, as they live spiritually now, shall live eternally hereafter, and never die the second or eternal death; on them that shall have no power, see John 6:40,
and let not his men be few; or, "though his men be few?" as Bishop Patrick chooses to render the words, and as they will bear, "vau", being sometimes so used, of which Noldius (h) gives instances; and the number of men in this tribe were but few in comparison of some others; and so those that see the Son of God and believe in him are but a small number; for all men have not faith. 2-Thessalonians 3:2
(h) Concord. part. Ebr. p. 292.

The order in which the tribes are here blessed, is not the same as is observed elsewhere. The blessing of Judah may refer to the whole tribe in general, or to David as a type of Christ. Moses largely blesses the tribe of Levi. Acceptance with God is what we should all aim at, and desire, in all our devotions, whether men accept us or not, 2-Corinthians 5:9. This prayer is a prophecy, that God will keep up a ministry in his church to the end of time. The tribe of Benjamin had their inheritance close to mount Zion. To be situated near the ordinances, is a precious gift from the Lord, a privilege not to be exchanged for any worldly advantage, or indulgence. We should thankfully receive the earthly blessings sent to us, through the successive seasons. But those good gifts which come down from the Father of lights, through the rising of the Sun of righteousness, and the pouring out of his Spirit like the rain which makes fruitful, are infinitely more precious, as the tokens of his special love. The precious things here prayed for, are figures of spiritual blessing in heavenly things by Christ, the gifts, graces, and comforts of the Spirit. When Moses prays for the good will of Him that dwelt in the bush, he refers to the covenant, on which all our hopes of God's favour must be founded. The providence of God appoints men's habitations, and wisely disposes men to different employments for the public good. Whatever our place and business are, it is our wisdom and duty to apply thereto; and it is happiness to be well pleased therewith. We should not only invite others to the service of God, but abound in it. The blessing of Naphtali. The favour of God is the only favour satisfying to the soul. Those are happy indeed, who have the favour of God; and those shall have it, who reckon that in having it they have enough, and desire no more.

Let Reuben live, and not die--Although deprived of the honor and privileges of primogeniture, he was still to hold rank as one of the tribes of Israel. He was more numerous than several other tribes (Numbers 1:21; Numbers 2:11). Yet gradually he sank into a mere nomadic tribe, which had enough to do merely "to live and not die." Many eminent biblical scholars, resting on the most ancient and approved manuscripts of the Septuagint, consider the latter clause as referring to Simeon; "and Simeon, let his men be few," a reading of the text which is in harmony with other statements of Scripture respecting this tribe (Numbers 25:6-14; Numbers 1:23; Numbers 26:14; Joshua 19:1).

The blessings upon the tribes commence with this verse. "Let Reuben live and not die, and there be a (small) number of his men." The rights of the first-born had been withheld from Reuben in the blessing of Jacob (Genesis 49:3); Moses, however, promises this tribe continuance and prosperity. The words, "and let his men become a number," have been explained in very different ways. מספּר in this connection cannot mean a large number (πολὺς ἐν ἀριθμῷ, lxx), but, like מספּר מתי (Deuteronomy 4:27; Genesis 34:30; Jeremiah 44:28), simply a small number, that could easily be counted (cf. Deuteronomy 28:62). The negation must be carried on to the last clause. This the language will allow, as the rule that a negation can only be carried forward when it stands with emphatic force at the very beginning (Ewald, 351) is not without exceptions; see for example Proverbs 30:2-3, where three negative clauses follow a positive one, and in the last the לא is omitted, without the particle of negation having been placed in any significant manner at the beginning. - Simeon was the next in age to Reuben; but he is passed over entirely, because according to Jacob's blessing (Genesis 49:7) he was to be scattered abroad in Israel, and lost his individuality as a tribe in consequence of this dispersion, in accordance with which the Simeonites simply received a number of towns within the territory of Judah (Joshua 19:2-9), and, "having no peculiar object of its own, took part, as far as possible, in the fate and objects of the other tribes, more especially of Judah" (Schultz). Although, therefore, it is by no means to be regarded as left without a blessing, but rather as included in the general blessings in Deuteronomy 33:1 and Deuteronomy 33:29, and still more in the blessing upon Judah, yet it could not receive a special blessing like the tribe of Reuben, because, as Ephraim Syrus observes, the Simeonites had not endeavoured to wipe out the stain of the crime which Jacob cursed, but had added to it by fresh crimes (more especially the audacious prostitution of Zimri, Numbers 25). Even the Simeonites did not become extinct, but continued to live in the midst of the tribe of Judah, so that as late as the eighth century, in the reign of Hezekiah, thirteen princes are enumerated with their families, whose fathers' houses had increased greatly (1-Chronicles 4:34.); and these families effected conquests in the south, even penetrating into the mountains of Seir, for the purpose of seeking fresh pasture (1-Chronicles 4:39-43). Hence the assertion that the omission of Simeon is only conceivable from the circumstances of a later age, is as mistaken as the attempt made in some of the MSS of the Septuagint to interpolate the name of Simeon in the second clause of Deuteronomy 33:6.

Let Reuben live - Though Reuben deserve to be cut off or greatly diminished and obscured, according to Jacob's prediction, Genesis 49:4, yet God will spare them and give them a name and portion among the tribes of Israel, and bless them with increase of their numbers. All the ancient paraphrasts refer this to the other world, so far were they from expecting temporal blessings only. Let Reuben live in life eternal, says Onkelos, and not die the second death. Let Reuben live in this world, so Jonathan and the Jerusalem Targum, and not die that death which the wicked die in the world to come.