18 But if you are led by the Spirit, you are not under the law.
19 The acts of the flesh are obvious: sexual immorality, impurity and debauchery; 20 idolatry and witchcraft; hatred, discord, jealousy, fits of rage, selfish ambition, dissensions, factions 21 and envy; drunkenness, orgies, and the like. I warn you, as I did before, that those who live like this will not inherit the kingdom of God.
As an introduction to the thought in these verses it will be useful to look back to 13, where Paul warns the Galatians against using liberty as an occasion for licence. It would seem that there were those in Galatia who had swung away from the barren legalism of the Judaisers' attitudes and position to an opposite extreme, distorting Paul's teaching on liberty into a licence for unlimited self-indulgence. It is one thing to quote Augustine's famous dictum, 'Love God and do what you like' - rightly understood Paul would certainly endorse this statement - but it is quite another to take 'do as you like' as a charter for licence and 'an occasion to the flesh', and fail to recognise that to 'love God' lays a far more stringent encirclement and circumscription on our behaviour than the law itself does. This can be seen very clearly in Jesus' teaching in the Sermon on the Mount: 'Ye have heard that it hath been said...but I say unto you...' - i.e. the law says the act is wrong, but love (Jesus) says that even the thought is wrong. The Christian doctrine of liberty never relaxes the sanction of the law, never ever! Christian freedom is 'freedom from' but not 'freedom to' - not freedom to indulge the flesh (13a), not freedom to exploit one's neighbour (13b), not freedom to break the law (14). Such a freedom would simply be bondage, and the nature of that bondage is graphically expressed in the ugly recital of the works of the flesh in 19-21.