1. Legalism - Keeping the Mosaic law which was only a shadow of Christ not the real thing. Now that they had the real thing they should not go back to the shadow.
2. Worship of angels - Angels are created beings who worship not the creator who alone is worthy of worship. Instead of submission to the one head who is Christ, false teachers were encouraging subjective worship of angels. Everyone does according to his experience.
3. Asceticism - Man-made rules of self denial that can be compared to others is no substitute for Christ. Only the righteousness of Christ satisfies God's standard and that is received by grace through faith.
These false teachings are still around today. We must not settle for substitutes or shadows. Christ alone is the real thing!
Walk with the Lord and get the real thing!!!