Sayyiduna Abdullah (may Allah be pleased with him) narrates that when the Prophet (peace and blessings of Allah be upon him) intended to relieve himself, he said: "Bring me three stones." I found two stones and a piece of dung for him. The Prophet (peace and blessings of Allah be upon him) took the two stones and threw away the piece of dung, and said: "This is impure."
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