When the Jews joined together they were able, through the power of God, to thoroughly defeat the enemy. Likewise, Christians ought to be of one mind and of one accord.
"Fulfil ye my joy, that ye be likeminded, having the same love, being of one accord, of one mind." - Phil 2:2
We too have a common enemy, one who lays in wait for us that he might attack us at our weakest moment. We need to band together as brothers and sister, as soldiers in the spiritual war against our advisory the devil.
Just as the Jews used their weapons to defeat those who would seek to destroy them, we have been given weapons of war. We've been given a full armor to wear to protect us, and to help us to fight and win the battle against this great adversary.