You cannot do anything for your salvation, but you must do something to manifest it, you must work out what God has worked in. Are you working it out with your tongue, and your brain and your nerves? If you are still the same miserable crosspatch, set on your own way, then it is a lie to say that God has saved and sanctified you.
Real slavery is living your life trying to gain favor; real freedom is knowing you already have favor - the difference is huge. The gospel frees us to work and live from the secure basis of faith, not fear…. And nothing could be more liberating.