Matthew Poole's Concise Commentary
Numbers 21:28
A fire, i.e. the fury of war, which is oft and fitly compared to fire here, as Isaiah 47:14 Amos 1:7,10,12,14 2:2,5; Heshbon; that city which before was a refuge and defence to all the country, now is turned into a great annoyance and a public mischief. Ar of Moab. Quest. How can this be, since Ar was yet in the hands of the Moabites, Deuteronomy 2:9,18,29 ? Answ.
1. This may be understood not of the city Ar, but of the people or the country subject or belonging to that great and royal city, as the Chaldee understands it.
2. Possibly Ar was taken by Sihon of the Moabites, but afterwards was either recovered by the Moabites, or upon the Israelites approach quitted by Sihon, gathering all his forces together that he might fight with the Israelites, and so repossessed by the Moabites.
3. This place may be thus rendered, It shall consume Ar of Moab, the past tense being put for the future, as is usual in prophetical passages; and so this may be the Amorites prediction or presage, that having taken Heshbon and its territories, they should now extend their victories to Ar of Moab, though they fell short of that hope, as ordinarily men do. The lords of the high places; either,
1. The princes or governors of the strong holds, which were frequently in high places, especially in that mountainous country, and which were in divers parts all along the river of Arnon; and having taken some of these, they promised to themselves that they should take all the rest, and so proceed further and further, till they had taken Ar itself. Or rather,
2. The priests and people that worshipped their god in their high places; which may seem more probable,
1. Because as the Israelites worshipped God, so the heathens worshipped Baal, in high places, Numbers 22:41, and particularly the Moabites are noted for so doing, Jeremiah 48:35.
2. Because amongst the eminent places of Moab there is mention of Bamoth-baal, or, of the high places of Baal, Joshua 13:17.