Musar zu Jirmejahu 6:15

The fourth quality is impudence. Know that the quality of impudence nullifies most of the worship of God, just as the prophet, Jeremiah, said (6:15), “They are not at all ashamed, neither know they how to blush.” For him who cannot be ashamed of his deeds before Him, the worship of God will not cleave to such a one, as Scripture says (1 Samuel 2:26), “And he increased favour both with the Lord and also with men.” Everyone who is modest before the Creator will be modest before every man. If this is so, then we can say that everyone who is impudent to men will also be impudent to the Creator. Therefore, every man must subdue his inclination to harbor this quality and remember the evil which exists in it. Let him be envious of the truly modest ones when he sees them or when he hears their praise on the tongue of every man. And if he wishes to remove this quality, let him accustom himself to humble his soul and be ashamed before all the children of man, and let him walk with bowed figure and with his eyes to the ground, and let him remember that impudence will destroy all of his service to God.