Sayyiduna Anas bin Malik (may Allah be pleased with him) reports that the Messenger of Allah (peace and blessings be upon him) said: "The rewards and good deeds of my Ummah were presented before me, even to the extent of a straw that a person removes from the mosque. And the sins of my Ummah were also presented before me, and I did not see any sin greater than that of a person who was given a verse or a surah and then he forgot it."
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