"For we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this world, against spiritual wickedness in high places." Ephesians 6:12
Billy Graham tells a story of a boxer who was engaged in a boxing match and was being badly beaten. Battered and bruised, he leaned over the ropes and said to his trainer, "Please throw in the towel! This guy is killing me!"
The trainer said, "Oh no, he's not. He's not even hitting you. He hasn't laid a glove on you!" And the boxer looked at him through swollen eyes and said, "Well then, I wish you'd watch that referee - somebody is sure hitting me!"
The danger in Spiritual Warfare is not when you are being beat up, because you know you're in a battle when you're battered. You may not know exactly who or where the blows are coming from; but you know you're in a fight.
No, the danger in Spiritual Warfare is when the devil is leaving you alone; when you are not having struggles, when temptations are few. It's then, when life seems to be going good, that devil has you where he wants you. Either you are spiritually dull and living for the devil's cause or you are being set up for a big fall.
Just ask David about it. After years of running from Saul and struggling to form a new nation, it was when things seemed to be good that David saw another man's wife bathing on the roof. In a matter of days, the devil had David just were he wanted him - knee deep in sin and sliding down quickly.
Never take the armor off. Never let down your guard. We're in a war that will last a lifetime.