Ephesians 4:26-27 says, ‘“In your anger do not sin”: Do not let the sun go down while you are still angry, and do not give the devil a foothold.’
The word “devil” only occurs again in this letter in 6:11 in the context of spiritual warfare against the “powers”. Paul, the author of Ephesians, believed that the “powers” were closely associated with the “devil”. Although the believers had been raised with Christ and seated in the heavenlies (2:6) they were still engaged in a struggle with the “powers” (6:12). 4:26-27 provides an example of one of the devil’s strategies (6:11) and how this warfare was to be fought against by believers.