“How can the ignorant teach others? How can the licentious make others modest? And how can the impure make others pure? If anyone hates peace, how can he make others peaceable ? Or if anyone has soiled his hands with baseness, how can he cleanse the impurities of another? We read also that if the blind lead the blind, both will fall into the ditch [Matt. 15:14]. But first correct yourselves, in order that, free from blame , you may be able to correct those who are subject to you.”

Pope Urban II