Amr bin Dinar relates that Tamim al-Dari (may Allah be pleased with him) asked Sayyiduna Umar (may Allah be pleased with him) for permission to tell stories (to preach), but he refused to permit him. He asked him again, and again he refused. Then he asked him a third time, and he said: "If you wish," and gestured with his hand, meaning a gesture of slaughtering.
Hadith Referenceالمعجم الكبير للطبراني / باب التاء / 1238