Christians believe that God is all powerful, omnipotent.  In other words, as Jesus says  in Matthew 19:26, “With God all things are possible.”   He is frequently referred to as “almighty.”  But, in Judges 1:19 we read,  “And the Lord was with Judah; and he drave out the inhabitants of the mountain; but could not drive out the inhabitants of the valley, because they had chariots of iron.”  Here there appears to be a contradiction.  Was God not able to drive out the inhabitants of the valley?   

The apparent contradiction is derived from a misreading of the verse.  The “he” who drove out the inhabitants of the mountain, but could not drive out the inhabitants was Judah, not God!  The reason they could not drive out the inhabitants of the valley is given – “because they had chariots of iron.”  Later God rebukes Israel for making a league with some of the inhabatants, and not driving them out as He had commanded (Judges 2:2).  “Wherefore,” said He, ‘I also said, I will not drive them out from before you; but they shall be as thorns in your sides, and their gods shall be a snare unto you'” (Judges 2:3).  They could not drive out the inhabitants of the valley because they did not trust God to help them.  There is no contradiction!  God is all powerful!