5 Slaves, obey your masters, with fear and trembling, as though they were Christ.
When you serve them, you are serving God.
11 Put on the armor of God to fight against the devil.
12 For we are not fighting against humans, but against principalities, powers, rulers of the darkness of this world, and against spiritual wickedness in high places.
Although Ephesians claims to have been written by Paul, most scholars think it was written after his death by one of his followers. Also, the words "to the saints which are in Ephesus" does not occur in the best manuscripts. Wikipedia: Authorship of the Pauline epistles - Ephesians
The prince of the power of the air (2:2)
Satan is the "prince of the power of the air." Until modern times Christians believed that Satan was responsible for storms and droughts.
Put on the armor of God to fight against the devil. (6:11)