We are fighting in a war!--Not with carnal weapons against carnal Man, but against spiritual forces. That war is going on all the time in the unseen sphere of the Spirit all around us and even in us!--That war is going on between God and the Devil, between Jesus and Satan, between the forces of good and the forces of evil, between the angels of God and the demons of the Devil, between the saints of God and the wicked departed spirits that follow Satan!
We're not just fighting evil people, but evil spirits who possess them! Therefore, we have to have weapons that are more powerful than normal physical, carnal weapons. We have to have powerful spiritual weapons. Our weapons are not carnal, but much more powerful, unto the tearing down of spiritual strongholds, fighting and opposing spiritual wickedness in the spiritual realm! (2Cor.10:4)
The Devil's forces are everywhere, and are on the constant lookout for us! So we must be on the lookout for them and avoid them the best we can. But don't be afraid of them, for "If God be for us, who can be against us?" (Rom.8:31)
Resist the Devil and he will flee from you! (Jam.4:7)