Should a man who committed the same sin many times and is still fighting against it be in leadership position?
Preachers are involved in helping people out of their sins. Elders are involved in keeping people faithful to the gospel. Given that Jesus said, "And why do you look at the speck in your brother's eye, but do not consider the plank in your own eye? Or how can you say to your brother, 'Let me remove the speck from your eye'; and look, a plank is in your own eye? Hypocrite! First remove the plank from your own eye, and then you will see clearly to remove the speck from your brother's eye" (Matthew 7:3-5). A person cannot properly deal with another person's sins until he has dealt with his own.