Joshua 17:18
But the mountain shall be thine; for it is a wood, and thou shalt cut it down: and the outgoings of it shall be thine: for thou shalt drive out the Canaanites, though they have iron chariots, and though they be strong. But the mountain shall be thine; for it is a wood, and thou shalt cut it down: and the outgoings of it shall be thine: for thou shalt drive out the Canaanites, though they have iron chariots, and though they be strong.
The reply was given to the children of Joseph, that is Ephraim together with the half-tribe of Manasseh, after they demanded more than one lot on the ground that they were a great people. It was a firm answer that met their complaint directly and did not grant their request for easier territory. Their existing lot was already rich and included the plain of Sharon, yet the Canaanites still held its towns. They shrank from the toil and danger of conquering what had been assigned them and wanted territory that was already subdued.
Joshua turned their own claim of greatness and power back upon them, requiring effort proportionate to their numbers and strength. Because they were a great people with great power, they were told to go up to the wood country in the land of the Perizzites and of the giants. There they were to cut down the wood for themselves and thereby enlarge their possession. Its outgoings, the surrounding cleared and opened districts, were to become theirs as well.
In the same answer their lack of faith and courage was exposed. They were commanded to drive out the Canaanites of the valley even though those enemies were strong and possessed iron chariots. The promise joined to the command was that through the pledged power of the God of Israel they were fully able to make their own way as their brethren had done. With the faith and courage of Caleb they need not fear iron chariots, however formidable the foe appeared.