Matthew 7:3

And why beholdest thou the mote that is in thy brother's eye, but considerest not the beam that is in thine own eye?

One who judges others is compared to a person presuming to cast a splinter out of his brother's eye while a plank is in his own eye! This is a vivid picture of a person who ignores his own grievous sins while trying to correct the relatively minor shortcomings of another. The mote and the beam represent the disparity between that which is tiny, insignificant, almost invisible, and that which is obvious, flagrant, and obtrusive. The mote hunter is the nitpicker, the specialist in fine, disputed points, who focuses on the most minute deviations while ignoring far more basic and important considerations.