hadith 6 of an-nawawi

Numan ibn Bashir reported: I heard the Messenger of Allah, peace and blessings be upon him, say:الْحَلَالُ بَيِّنٌ وَالْحَرَامُ بَيِّنٌ وَبَيْنَهُمَا مُشَبَّهَاتٌ لَا يَعْلَمُهَا كَثِيرٌ مِنْ النَّاسِ فَمَنْ اتَّقَى الْمُشَبَّهَاتِ اسْتَبْرَأَ لِدِينِهِ وَعِرْضِهِ وَمَنْ وَقَعَ فِي الشُّبُهَاتِ كَرَاعٍ يَرْعَى حَوْلَ الْحِمَى يُوشِكُ أَنْ يُوَاقِعَهُ أَلَا وَإِنَّ لِكُلِّ مَلِكٍ حِمًى أَلَا إِنَّ حِمَى اللَّهِ فِي أَرْضِهِ مَحَارِمُهُ أَلَا وَإِنَّ فِي الْجَسَدِ مُضْغَةً إِذَا صَلَحَتْ صَلَحَ الْجَسَدُ كُلُّهُ وَإِذَا فَسَدَتْ فَسَدَ الْجَسَدُ كُلُّهُ أَلَا وَهِيَ الْقَلْبُThat which is lawful is plain and that which is unlawful is plain and between the two of them are doubtful matters about which not many people know. Thus he who avoids doubtful matters clears himself in regard to his religion and his honor, but he who falls into doubtful matters falls into that which is unlawful, like the shepherd who pastures around a sanctuary, all but grazing therein. Truly every king has a sanctuary, and truly Allah’s sanctuary is His prohibitions. Truly in the body there is a morsel of flesh which, if it be whole, all the body is whole and which, if it be diseased, all of it is diseased. Truly it is the heart.
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