What does it mean to “put on your new nature”? It means that your conduct should match your faith. If you are a Christian, you should act like it.
To be a Christian means more than just making good resolutions and having good intentions; it means taking the right actions. This is a straightforward step that is as simple as putting on your clothes.
Put on your new nature, and be renewed as you learn to know your Creator and become like him. – Colossians 3:10