Jesus knew the hearts of men (John 2:24–25) and he urged us to be perceptive in assessing others (Matthew 7:15–20.). Leaders must know who is fit for what kind of work. Good leaders have good noses. They can snoop out barnacles in a hurry; that is, people who are forever listening but never learning or changing. They can detect potential when they see it in a beginner. They can hear in a short time the echoes of pride and hypocrisy and worldliness. The spiritual leader steers a careful course between the dangers of rigid pigeonholing on the one hand and indifference on the other hand.