Verse 21: (Deut. 3:10) And all the cities of the plain, and all the kingdom of Sihon king of the Amorites, which reigned in Heshbon, (Num. 21:24) whom Moses smote (Num. 31:8) with the princes of Midian, Evi, and Rekem, and Zur, and Hur, and Reba, which were dukes of Sihon, dwelling in the country.
[And all the cities in the open plain, and all the kingdoms of Sihon] Or, and the whole, or entire, kingdom of Sihon. [Thus all interpreters.] But only half of this kingdom fell to the Reubenites, the rest to the Gadites (Masius). Therefore, he does not mean to say that the Reubenites alone occupied the entire kingdom of Sihon, but that these cities all together were pertaining to the kingdom of Sihon (Lapide and Bonfrerius nearly out of Masius). Therefore, thus I translate, all the cities of the plain, which all were of the kingdom of Sihon, etc. (Masius). The ו/and [in וְכָל, and all] he takes for אֲשֶׁר/which; which is not unusual, but here appears harsh to me, and forced. Or, all the kingdom is here used of the middle part, as in some places of the greater part, and in other places of the lesser (Drusius). Now, he relates that all those places belonged to Sihon, lest any should be thought to be taken by the Moabites (Masius). Or, if you prefer, say that the Reubenites occupied all the cities and all the kingdoms of Sihon together that were contained within the borders allotted to them; a limitation of which sort also appears necessarily to be understood below in verse 25 (Bonfrerius).
The cities of the plain; opposed to the foregoing cities of the mountain of the valley. All the kingdom of Sihon; a synecdochical expression, for a great part of it; in which sense we read of all Judea, and all the region round about Jordan, Matthew 3:5, and all Galilee, Matthew 4:23, and many others. Or, which all were the kingdoms of Sihon, that is, belonged to his kingdom. The Hebrew conjunction and is oft put for the relative particle which, as Judges 2:21; Proverbs 19:1; Ecclesiastes 6:12.
[Whom Moses smote with the princes of Midian] Upon the occasion of the mention of Sihon, there is a digression to the slaughter of the Midianite nobles (Masius). These are said to have been killed with Sihon, not because they were killed in the same battle, for Sihon is read to have been overthrown in Numbers 21, but these Midianite princes in Numbers 31; but because they were overthrown by the same Moses, with a like defeat, at almost the same time (Bonfrerius).
With the princes of Midian; not in the same time or battle, as appears by comparing Numbers 21:23, 24 with Numbers 31:8, but in the same manner. And they are here mentioned, partly because they were slain not long after, and upon the same occasion, even their enmity against Israel; and partly because of their relation and subjection to Sihon, as it here follows.
[Dukes of Sihon (thus Munster, Pagnine, Arabic), נְסִיכֵ֣י סִיח֔וֹן] Prefects of Sihon (Masius, Montanus), or, toparchs (Junius and Tremellius), or, princes (Jonathan, Syriac, Tigurinus). They are thus called because they were Sihon’s subjects yielding taxes and tribute (Lapide). Perhaps, together with the Moabites and Ammonites, with whom the Midianites were sharing borders, were Sihon’s subjects yielding taxes (although not subject to him by full right and authority). This is made probable both from this passage, and from this, that Sihon by war with the Moabites and Ammonites had wrested away a part their territory, who, hence being driven by power, does not appear to have been about to leave off, unless they at least be made subject to him as taxpayers: which same thing was likely done concerning the neighboring Midianites (Bonfrerius). In Numbers 31, these are indeed called the kings of the Midianites. But thus the Hebrews call those that have small domain, as the Latins call them regulos, petty kings (Masius). That is, They were Kings in Midian, but subjects of the empire of the great King Sihon (Munster). Now, these came to the aid of Sihon, either, as those subject to tribute (Lapide); or, because they had the Israelites as a common enemy (Masius, Drusius). Either, they had only prepared aid (Bonfrerius); or, if they brought it, with Sihon killed, they escaped by flight to their Midianites, and together with those they perished a little later (Masius, Lapide, Bonfrerius). It is not strange that the Midianites attended to Sihon, since Balak made use of them in hiring Balaam, Numbers 22:4, 5. It is likely that the Midianites excelled in handling matters with singular industry (Masius).
Dukes of Sihon. Question. How could they be so, when they were kings of Midian? Numbers 31:8. Answer. There were divers petty kings in those parts, which were subject to greater kings; and such these were, but are here called dukes or princes of Sihon, because they were subject and tributaries to him, and therefore did one way or other assist Sihon in this war, though they were not killed at this time. It is probable, that when Sihon destroyed those Moabites which dwelt in these parts, he frighted the rest of them, and with them their neighbours and confederates the Midianites, into some kind of homage or tribute, which they were willing to pay to him.
[Inhabitants of the land (thus Pagnine, Montanus, Septuagint, Jonathan, similarly Munster, Tigurinus, Syriac)] Or, dwelling in that land (Arabic, Tigurinus, similarly Junius and Tremellius), that is, not foreigners, generals summoned by Sihon from elsewhere. This is added, so that their fervent zeal in fighting for the homeland might be signified, which is wont to be far less in protecting the borders of stangers (Bonfrerius). Kimchi supposes that Sihon, while his affairs were prospering, also ruled among the Midianites, and that therefore those are called the prefects of Sihon, although they were Midianites (Masius).
Dwelling in the country; Hebrew, inhabiting that land, namely, Midian, last mentioned; whereby he signifies, that though they were subject to Sihon, yet they did not dwell in his land, but in another.
 Hebrew: וְכֹל֙ עָרֵ֣י הַמִּישֹׁ֔ר וְכָֽל־מַמְלְכ֗וּת סִיחוֹן֙ מֶ֣לֶךְ הָאֱמֹרִ֔י אֲשֶׁ֥ר מָלַ֖ךְ בְּחֶשְׁבּ֑וֹן אֲשֶׁר֩ הִכָּ֙ה מֹשֶׁ֜ה אֹת֣וֹ׀ וְאֶת־נְשִׂיאֵ֣י מִדְיָ֗ן אֶת־אֱוִ֤י וְאֶת־רֶ֙קֶם֙ וְאֶת־צ֤וּר וְאֶת־חוּר֙ וְאֶת־רֶ֔בַע נְסִיכֵ֣י סִיח֔וֹן יֹשְׁבֵ֖י הָאָֽרֶץ׃
 Hebrew: וְכֹל֙ עָרֵ֣י הַמִּישֹׁ֔ר וְכָֽל־מַמְלְכ֗וּת סִיחוֹן֙ .
 Judges 2:21: “I also will not henceforth drive out any from before them of the nations which Joshua left when he died (וַיָּמֹת, or, who died)…”
 Proverbs 19:1: “Better is the poor that walketh in his integrity, than he that is perverse in his lips, and is a fool (וְה֣וּא כְסִֽיל׃, or, who is a fool).”
 Ecclesiastes 6:12: “For who knoweth what is good for man in this life, all the days of his vain life which he spendeth as a shadow (וְיַעֲשֵׂ֣ם כַּצֵּ֑ל)? for who can tell a man what shall be after him under the sun?”
 That is, the ruler of a local district.
 Hebrew: יֹשְׁבֵ֖י הָאָֽרֶץ׃.