PRACTICE WHAT YOU PREACH
Muhammad was very fond of eating dates. One day a mother brought her son to him, complaining that the boy ate a lot of dates every day and so suffered from dysentery. The boy refused to obey his parents, and told them that he would not eat dates only if Muhammad told him not to do so. Muhammad could not tell the boy not to eat dates, when he himself was very fond of them and ate a lot of them. He told the mother and son to come back after a few days. Meanwhile, Muhammad stopped eating dates and when the mother came with the boy, he told the boy not to eat dates. The boy obeyed at once.
Unless one has mastered a virtue, he has no right or authority to teach or preach it to others.