Psalms 136:19

Sihon king of the Amorites
A strong and warlike people, and their king a great and mighty one; see ( Psalms 135:11 ) ;

for his mercy [endureth] for ever;
since this king would not suffer Israel to go through his borders, but came out and fought against them; and had not the Lord smote him, they must have fallen a prey into his hands, ( Numbers 21:23 ) .