10For we are God's workmanship, created in Christ Jesus to do good works, which God prepared in advance for us to do.
We don't do good works for us to be saved. We were saved to do good works.
These works are to be done in 'fullness of time'. God's preparation includes time, location, method.
Such works do not spring from our own strength or good intentions. They have been prepared by God even before; He works them 'in'. We then work them 'out'