Fruit bearing is a result of spiritual wisdom and understanding, according to Col 1.10:
bearing fruit in every good work
I wonder if the difference between having knowledge of his will WITHOUT spiritual wisdom and understanding, and having knowledge of his will WITH spiritual wisdom and understanding is that we can know His will and not do it.
Perhaps spiritual wisdom and understanding are the spark plugs inside of us, that set us into action to do His will.
And so, from the day we heard, we have not ceased to pray for you, asking that you may be filled with the knowledge of his will in all spiritual wisdom and understanding, so as to walk in a manner worthy of the Lord, fully pleasing to him bearing fruit in every good work
Col 1.9-10
John tells us that trees--and people--that do not bear fruit, make for good firewood.
Jesus taught us that a tree--and a beloved nation--that are not producing fruit, are to be cursed and dried up.
We must be bearing fruit.