Abu Wa'il says: Sayyiduna Ammar bin Yasir (may Allah be pleased with him) delivered a sermon to us; it was very eloquent and brief. When he descended from the pulpit, we said: O Abu al-Yaqzan! Indeed, you have delivered a very eloquent and brief sermon; you could have made it a little longer. In response, he said: In fact, I heard the Messenger of Allah (peace and blessings be upon him) say: Surely, the lengthening of a man's prayer and the shortening of his sermon are signs of his understanding. Therefore, you should make the prayer long and the sermon short, for indeed, some speech is (as effective as) magic.