"You need to repent"
"You must put that practice to death"
"You must die"
- more like it
"You have been crucified with Christ, the world is crucified to you and you to the world."
- now you're cooking with Holy Ghost power.
Meditating on Galatians 6:14 this morning I reckon we need to be much more radical in our language about 'sanctification'. Even talking about 'mortification' can get us off the hook if we imagine ourselves as some tutting fashionista putting off the old man like a bad suit. It is a bad suit. But it's also me. Taking it off is like flesh peeling from bones. It's me that has to die not simply some habit or attitude.
But then I'm reminded - I'm already dead. I'm already crucified with Jesus. From baptism onwards I've been united with Him in His death. I'm carrying my cross daily - it's Christ's gift to me, releasing me from every worldly claim. I owe this world exactly what a corpse owes it - jack squat.
Realising this again is repentance (change of mind). I am realigned with reality - living is dying; dying is living. But when united with Jesus it's always a fruitful death - pruned branches bearing fruit for God.
So don't give up your sin, don't reorder your priorities, don't resolve to try harder. Just die. It's the very essence of your life. .
(PS I'm away from a computer right now so unable to respond to comments).