Sayyiduna Abu Sa'id Khudri (may Allah be pleased with him) narrates: The Prophet Muhammad (peace and blessings be upon him) led us in prayer. When he had performed the prayer, he took off his shoes and placed them to his left. The people present also took off their shoes. When the Prophet (peace and blessings be upon him) completed the prayer, he asked: Why did you take off your shoes? The people replied: We saw you take off your shoes, so we also took ours off. The Prophet (peace and blessings be upon him) said: I did not take them off due to any fault, but rather Jibreel informed me that there was impurity on them. When any person comes to the mosque, he should examine his shoes; if there is impurity on them, he should clean it off.