Their gods are gods of the hills - It is very likely that the small Israelitish army availed itself of the heights and uneven ground, that they might fight with greater advantage against the Syrian cavalry, for Ben-hadad came up against Samaria with horses and chariots, 1 Kings 20:1. These therefore must be soon thrown into confusion when charging in such circumstances; indeed, the chariots must be nearly useless.
Let us fight against them in the plain - There our horses and chariots will all be able to bear on the enemy, and there their gods, whose influence is confined to the hills, will not be able to help them. It was a general belief in the heathen world that each district had its tutelary and protecting deity, who could do nothing out of his own sphere.
Their gods are gods of the hills - The local power and influence of deities was a fixed principle of the ancient polytheism. Each country was considered to have its own gods; and wars were regarded as being to a great extent struggles between the gods of the nations engaged in them. This is apparent throughout the Assyrian inscriptions. Compare also 2 Kings 18:33-35; 2 Kings 19:12. The present passage gives an unusual modification of this view. The suggestion of the Syrian chiefs may have been a mere politic device - they being really anxious, “an military grounds,” to encounter their enemy on the plain, where alone their chariots would be of much service. In the plain the Israelites had always fought at a disadvantage, and had proved themselves weaker than on the hills (see Judges 1:19, Judges 1:27, Judges 1:34).