Having begun by the Spirit, are you now being perfected by the flesh? Paul confronts the Galatians with an absurd logic: they began through the Spirit and are now trying to continue through their own strength.
In the New Covenant this principle stands: how you began is how you continue. Through the Spirit. Your new identity was not created by your effort and is not maintained by your effort either.
When you notice today that you fall back into striving, remember: the Spirit began, the Spirit completes. You may flow with it, not fight against it.