Here's the rub. If the Israelite army is so outnumbered and outgunned, why do the Arameans wait seven days? You would think they would join battle right away. Again, the commentaries I consulted ignored it. Here's the text:
So in the spring of the year, Ben-hadad assembled the Arameans and marched up to Aphek to fight with Israel. Now the Israelites had already been assembled and provisioned, so they went to engage the Arameans. The Israelites camped before them like two small flocks of goats, but the Arameans filled the land.<idle musing>
Then the man of God came forward and said to Israel’s king, “This is what the Lord says: Because the Arameans said that the Lord is a god of the mountains but not a god of the valleys, I am handing this whole great army over to you. Then you will know that I am the Lord.”
The two armies camped opposite each other for seven days. On the seventh day, the battle began. The Israelites attacked and destroyed one hundred thousand Aramean foot soldiers in a single day. 1 Kings 20:26–29 CEB
Well, I have a tentative answer (you knew that was coming, didn't you!). As I repeatedly say, in the ancient world, no battle was ever fought without consulting the gods. My theory is that the omens were bad. Bad omens, no battle.
Don't underestimate the psychological power of bad omens in the ancient world (or in the modern one, either—just take a look at the sports world...). Consider the interpretation of the Midianite dream in the story of Gideon (Judges 7:13–14); bad omen/portent = disaster.
I submit that the Arameans were waiting for good omens and the Israelites were waiting for the prophets to say it was time to attack...what do you think? Got a better idea? Just an