Sayyiduna Abu Sa'id Khudri (may Allah be pleased with him) narrates that the Messenger of Allah (peace and blessings of Allah be upon him) said: "Satan comes to one of you during his prayer and says, 'You have broken your wudu.' So he should say to him, 'You have lied,' unless he hears a sound with his ear or perceives a smell with his nose." Imam Abu Bakr (may Allah have mercy on him) says that « فَلْیَقُلْ کَذَبْتَ » he should say, "You have lied." By this, the Prophet (peace and blessings of Allah be upon him) meant that the worshipper should say it in his heart (so that the whispering goes away), not with his tongue, because it is not permissible for the worshipper to say « کَذَبْتَ » with his tongue (that is, speaking is prohibited for him).
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