Sunan Ibn Majah, Book 36, Hadith 59 (In-Book)

While on the pulpit, pointing with this fingers towards his ears, Nu’man bin Bashir said: “I heard the Messenger of Allah say: ‘That which is lawful is plain and that which is unlawful is plain, and between them are matters that are not clear, about which not many people know. Thus he who guards against the unclear matters, he clears himself with regard to his religion and his honor. But he who falls into the unclear matters, he falls into that which is unlawful. Like the shepherd who pastures around a sanctuary, all but grazing therein. Every king has a sanctuary. And beware! Allah’s sanctuary is His prohibitions. Beware! In the body there is a piece of flesh which, if it is sound, the whole body will be sound, and if it is corrupt, the whole body will be corrupt. It is the heart.’”

حَدَّثَنَا عَمْرُو بْنُ رَافِعٍ، حَدَّثَنَا عَبْدُ اللَّهِ بْنُ الْمُبَارَكِ، عَنْ زَكَرِيَّا بْنِ أَبِي زَائِدَةَ، عَنِ الشَّعْبِيِّ، قَالَ سَمِعْتُ النُّعْمَانَ بْنَ بَشِيرٍ، يَقُولُ عَلَى الْمِنْبَرِ وَأَهْوَى بِإِصْبَعَيْهِ إِلَى أُذُنَيْهِ سَمِعْتُ رَسُولَ اللَّهِ ـ صلى الله عليه وسلم ـ يَقُولُ ‏ "‏ الْحَلاَلُ بَيِّنٌ وَالْحَرَامُ بَيِّنٌ وَبَيْنَهُمَا مُشْتَبِهَاتٌ لاَ يَعْلَمُهَا كَثِيرٌ مِنَ النَّاسِ فَمَنِ اتَّقَى الشُّبُهَاتِ اسْتَبْرَأَ لِدِينِهِ وَعِرْضِهِ وَمَنْ وَقَعَ فِي الشُّبُهَاتِ وَقَعَ فِي الْحَرَامِ كَالرَّاعِي حَوْلَ الْحِمَى يُوشِكُ أَنْ يَرْتَعَ فِيهِ أَلاَ وَإِنَّ لِكُلِّ مَلِكٍ حِمًى أَلاَ وَإِنَّ حِمَى اللَّهِ مَحَارِمُهُ أَلاَ وَإِنَّ فِي الْجَسَدِ مُضْغَةً إِذَا صَلُحَتْ صَلُحَ الْجَسَدُ كُلُّهُ وَإِذَا فَسَدَتْ فَسَدَ الْجَسَدُ كُلُّهُ أَلاَ وَهِيَ الْقَلْبُ ‏" ‏ ‏.‏

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