Is "only" OK here? Is this grammatically OK? Should I take "can" out?
As you witness His faithfulness in your life, you can learn to let go of trusting only in yourself and begin placing your trust in Him.
It's fine. You can also move it to just before 'yourself', which doesn't change the meaning but gives a little different 'feel' to the phrase.
...of trusting in only yourself...
I would keep 'can', because it shows the possibility and not necessarily the absolute learning.
|link comment||answered May 06 '13 at 14:03 Lewis Neidhardt Grammarly Fellow|