And it came to pass, as they fled from before Israel, and were in the going down to Beth-horon, that the LORD cast down great stones from heaven upon them unto Azekah, and they died: they were more which died with hailstones than they whom the children of Israel slew with the sword.
Joshua's promise to the Gibeonites bound him not merely to spare them but to defend them as his own servants sheltering under God's wings. When he moved from Gilgal to relieve them, he walked in duty, and God's word settled all fear: those marked for destruction can neither resist nor escape, however many kings confederate against you.
AI summary
Commenting on Joshua 10:7-14
And it came to pass, as they fled before Israel, and were in the going down to Bethhoron,.... The descent of it on that side towards Azekah, and which was also a very narrow passage, of which Josephus (s) makes mention.
GOD FIGHTS AGAINST THEM WITH HAILSTONES. (Jos 10:10-11) the Lord discomfited them--Hebrew, "terrified," confounded the Amorite allies, probably by a fearful storm of lightning and thunder. So the word is usually employed (Sa1 7:10; Psa 18:13; Psa 144:6). and slew them with a great slaughter at Gibeon--This refers to the attack of the Israelites upon the besiegers.
Commenting on Joshua 10:10-11