For {k} Heshbon was the city of Sihon the king of the Amorites, who had fought against the former king of Moab, and taken all his land out of his hand, even unto Arnon.

(k) For if it had been the Moabites, the Israelites might not have possessed it, De 2:9.

Wesley's Notes

21:26 Was the city of Sihon - This is added as a reason why Israel took possession of this land, because it was not now the land of the Moabites, but in the possession of the Amorites. The former king - The predecessor of Balak, who was the present king. See the wisdom of providence, which prepares long before, for the accomplishing God's purposes in their season! This country being designed for Israel, is before - hand put into the hand of the Amorites, who little think they have it but as trustees, till Israel comes of age. We understand not the vast reaches of providence: but known unto God are all his works!

Jamieson-Fausset-Brown Bible Commentary

26. Heshbon-(So 7:4)-situated sixteen English miles north of the Arnon, and from its ruins it appears to have been a large city.

Matthew Henry's Concise Commentary

21:21-35 Sihon went with his forces against Israel, out of his own borders, without provocation, and so ran upon his own ruin. The enemies of God's church often perish by the counsels they think most wisely taken. Og, king of Bashan, instead of being warned by the fate of his neighbours, to make peace with Israel, makes war with them, which proves in like manner his destruction. Wicked men do their utmost to secure themselves and their possessions against the judgments of God; but all in vain, when the day comes on which they must fall. God gave Israel success, while Moses was with them, that he might see the beginning of the glorious work, though he must not live to see it finished. This was, in comparison, but as the day of small things, yet it was an earnest of great things. We must prepare for fresh conflicts and enemies. We must make no peace or truce with the powers of darkness, nor even treat with them; nor should we expect any pause in our contest. But, trusting in God, and obeying his commands, we shall be more than conquerors over every enemy.