I have been reading Dallas Willard's, The Divine Conspiracy. Note what he says about the beam (or board) in our own eyes.
"Condemnation is the board in our eye. He knows that the mere fact that we are condemning someone shows our heart does not have the kingdom rightness he has been talking about. Condemnation, self-righteousness, blinds us to the reality of the other person. We cannot 'see cleary' how to assist our brother, because we cannot see our brother. And we will never know how to truly help him until we have grown into the kind of person who does not condemn. Period. 'Getting the board our' is not a matter of correcting something that is wrong in our life so that we will be able to condemn our dear ones better—more effectively, so to speak" (p. 224).