When Joshua was by Jericho, he lifted up his eyes and looked, and behold, a man was standing before him with his drawn sword in his hand. And Joshua went to him and said to him, Are you for us, or for our adversaries? And he said, No; but I am the commander of the army of the LORD. Now I have come. … -- Joshua 5:13-14
Whoever is not with me is against me, and whoever does not gather with me scatters (Matthew 12:30).For the one who is not against us is for us (Mark 9:40).