And Sihon would not suffer Israel to pass through his border,
&c.] Because he could not trust them, and confide in the promises they made, and thought it not safe to let such a body of people into any part of his dominions, ( Judges 11:20 ) and chiefly because his heart was hardened by the Lord, that he might be delivered into the hands of Israel, as was determined, ( Deuteronomy 2:30 ) :
but Sihon gathered all his people together;
all that were able to bear arms out of his cities, and which made no doubt a very numerous and powerful army; but then these being defeated, as they were, it became more easy to the Israelites to take their cities, where there were none left but women and children:
and went out against Israel into the wilderness;
the wilderness of Kedemoth; not content to reject a peaceable message, he went out in an hostile manner against Israel, even out of his own dominions; so that he was the aggressor and unprovoked, which made his ruin appear the more just, and the children of Israel to have a better claim to his country conquered by them:
and he came to Jahaz;
a frontier town in the land of Moab, see ( Isaiah 15:4 ) ( Jeremiah 48:34 ) and which, according to Bunting F16, was sixteen miles from Abarim:
and fought against Israel;
at the above place, where they had a pitched battle.