‘Wherein previously you walked according to the course of this world, according to the prince of the power of the air, of the spirit that now works in the sons of disobedience.'
They had been guilty at three levels. They were guilty of personal sin (‘your trespasses and sins'), they were not dupes but rebels; they were guilty of following the dictates of the world (‘the course of this world'), allowing themselves to be carried along either unthinkingly or deliberately in the stream of humanity; they were guilty of allowing themselves to be swayed by Satan (‘the spirit who works in disobedient people'), by closing their minds to the light when it came.
‘You walked.' They had walked in sin because they had walked in darkness (John 8:12; John 11:10), in the vanity of their mind (Ephesians 4:17), following the dictates of the flesh (Romans 8:1; Romans 8:4). This was their way of life. This is in contrast to those who walk in the light (John 12:35), in the steps of faith (Romans 4:12), in accordance with the Spirit (Romans 8:1; Romans 8:4), in newness of life (Romans 6:4). This is the Christian's way of life.
‘According to the course (the age) of this world.' They had followed the spirit of the age and had been tied down by, and submerged in, the ideas of an unbelieving world. To walk with the majority view is to walk in sin because man is sinful.
‘According to the prince of the power of the air, of the spirit who now works in the sons of disobedience.' While they may not have been aware of it they were also carried along in their ways by spiritual forces, the spirit who now works in disobedient people (‘The sons of disobedience' means those who follow and are taken up with disobedience). So three factors were involved; their own choice, the influence of the age, and the workings of Satan.
‘The prince of the power of the air.' A controlling spirit over ‘the power of the air'. In Colossians 1:13 ‘power' is equivalent to ‘kingly rule', for it compares ‘the power of darkness' with ‘the kingly rule of His beloved Son'. Thus the idea may be of a prince ruling over ‘a kingdom', a kingdom of spiritual beings not naturally of this earth, and of all who walk in disobedience. ‘The air' may be seen as a kind of No Man's Land, almost equivalent to the ‘heavenlies', but excluded from them, and thus a minor spiritual sphere, from which Satanic forces attack the heavenlies (Ephesians 6:12). It is the sphere of those who do not know God or walk with Him. We can compare how in Revelation Satan was seen as attacking the forces of Heaven and was cast out of the heavenly realm (Revelation 12:8 compare Luke 10:18). In our view both these verses in Revelation are speaking of the time when Jesus was resurrected (see Revelation).
Alternately the ‘power of the air' may be seen as evil winds, which may tie in with the idea of ‘winds' of false doctrine tossing men to and fro like leaves (Ephesians 4:14). Winds are often symbols of disaster (see especially Job 1:19 with 12 where such were specifically Satan's work).
‘The spirit who now works in the sons of disobedience.' This can only be the Devil, Satan, the adversary and tempter (Matthew 4:10; Matthew 16:23; Mark 4:15; Luke 22:3; Acts 5:3; Acts 26:18; 2 Corinthians 11:14; Ephesians 4:26; Ephesians 6:11; 1Ti 5:15; 1 Peter 5:8; 1 John 3:8-10). He himself is in rebellion against God, and he has thus brought others into that same spirit of rebellion.