So then, you will know them by their fruits.
This proverb is often quoted to show how you can tell a person's nature by looking at their actions. Jesus, however, seems to use this verse to communicate the exact opposite.
In Matthew 7:21-23 Christ gives an example of people who look at their “fruits” and believe that they are righteous, only to be told by the Lord “I never knew you.” How can we have any assurance when our “fruits” can be so misleading?
When the harvest comes, I will know myself and others by our fruit. Until then I need to realize how little I know and place my faith in the One who knows me.