“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.”
King James Version (KJV)
6:12 For our wrestling is not only, not chiefly, against flesh and blood - Weak men, or fleshly appetites. But against principalities, against powers - The mighty princes of all the infernal legions. And great is their power, and that likewise of those legions whom they command. Against the rulers of the world - Perhaps these principalities and powers remain mostly in the citadel of their kingdom of darkness. But there are other evil spirits who range abroad, to whom the provinces of the world are committed. Of the darkness - This is chiefly spiritual darkness. Of this age - Which prevails during the present state of things. Against wicked spirits - Who continually oppose faith, love, holiness, either by force or fraud; and labour to infuse unbelief, pride, idolatry malice, envy, anger, hatred. In heavenly places - Which were once their abode, and which they still aspire to, as far as they are permitted.
Eph 6:12 For we wrestle. Fights then were a hand to hand grapple. Not against flesh and blood. While flesh and blood may seem to assail us, the real enemies are evil spiritual powers. Against principalities, against powers. These terms designate different rank of evil spirits. These were fallen angels (see Ro 8:38). The same terms are applied to the different ranks of holy angels in Eph 1:21. Against the rulers of the darkness of this world. Satan is described as the ruler of this world (Joh 12:31 14:30 16:11) and the god of this world (2Co 4:4). He uses for his dominion not only evil spirits, but wicked men, and his sway is darkness rather than light. Against spiritual wickedness in high [places]. "Spiritual [hosts] of wickedness" (Revised Version). It is likely that the meaning is the same as in Eph 2:2 The high places, the air, is a dwelling place and medium of these evil influences.