Sayyiduna Abdullah (may Allah be pleased with him) narrates: The Prophet Muhammad (peace and blessings be upon him) taught me Surah Ar-Rahman. One day, I came to the mosque in the evening, and some people came and sat near me. I said to one of them: Recite (the Qur'an) before me. So he recited some words in a manner that I had not learned. I asked: Who taught you this recitation? He replied: The Messenger of Allah taught me this recitation. Then we set out and presented ourselves before the Prophet Muhammad (peace and blessings be upon him). I said: We have differed regarding the recitation. Upon hearing this, the blessed face of the Prophet Muhammad (peace and blessings be upon him) changed, and when I mentioned the difference, he was greatly saddened by it. He said: The people before you were destroyed because of their differences. Then he instructed Sayyiduna Ali (may Allah be pleased with him), and he said: Indeed, the Messenger of Allah commands you that each of you should recite in the manner in which he was taught, because the people before you were destroyed due to their differences. The narrator says: Then we left from there, and each of us would recite in the manner he had learned, and his companion would not recite in his manner.