Christian growth doesn’t happen by working hard to get something you don’t have. Christian growth happens by working hard to live in the reality of what you do have.
I used to think that when the Bible tells us to work out our salvation, it meant go out and get what you don’t have-get more patience, get more strength, get more joy, get more love, and so on. But after reading the Bible more carefully I now understand that real gospel fruit happens, not as we “work harder” but only as we continually rediscover the gospel. You could put it this way: rediscovering the gospel is the hard work we’re called to.