(10) And (the children of) mount Seir.--The Maonites are here so called apparently, and thus identified as an Edomite people. (See on 2Chronicles 20:1.)

Whom thou wouldest not let Israel invade.--See the respective prohibitions (Deuteronomy 2:4; Deuteronomy 2:9; Deuteronomy 2:19.) Comp. also (Numbers 20:14-21) the king of Edom's refusal of a passage through his territory (Judges 11:15, seq.) These tribes were recognised as the kindred of Israel, as being sons of Esau and sons of Lot. (The Syriac has "mount Gebel," i.e., Geb?l, the name of a tribe living in the northern part of mount Seir, Psalm 73:8.)

20:1-13 In all dangers, public or personal, our first business should be to seek help from God. Hence the advantage of days for national fasting and prayer. From the first to the last of our seeking the Lord, we must approach him with humiliation for our sins, trusting only in his mercy and power. Jehoshaphat acknowledges the sovereign dominion of the Divine Providence. Lord, exert it on our behalf. Whom should we seek to, whom should we trust to for relief, but the God we have chosen and served. Those that use what they have for God, may comfortably hope he will secure it to them. Every true believer is a son of Abraham, a friend of God; with such the everlasting covenant is established, to such every promise belongs. We are assured of God's love, by his dwelling in human nature in the person of the Saviour. Jehoshaphat mentions the temple, as a token of God's favourable presence. He pleads the injustice of his enemies. We may well appeal to God against those that render us evil for good. Though he had a great army, he said, We have no might without thee; we rely upon thee.And now, behold, the children of Ammon, and Moab, and Mount Seir, whom thou wouldest not let Israel invade, when they came out of the land of Egypt,.... Charging them not to meddle with them, nor take any of their lands from them, Deuteronomy 2:5,

but they turned from them, and destroyed them not; in obedience to the divine command, when it was in their power to have done it.