Bulugh al-Maram, Book 16, Hadith 1511 (English) ⓘ

An-Nu’man bin Bashir (RAA) narrated, I heard Allah‘s Messenger saying, (Nu'man pointed with his two fingers to his ears) ‘Both lawful (Halal) and unlawful things (Haram) are evident but in between them there are doubtful things·and most people have no knowledge about them. So he, who saves himself from these doubtful things, saves his religion and his honor (i.e. keeps them blameless). And he who indulges in these doubtful things is like a shepherd who pastures (his animals) near the Hima (private pasture) of someone else and at any moment he is liable to get in it. (O people!) Beware! Every king has a Hima and the Hima of Allah on the earth is what He declared unlawful (Haram). Beware In the body there is a piece of flesh if it becomes sound and healthy, the whole body becomes sound and healthy but if it gets spoilt, the whole body gets spoilt and that is the heart.” Agreed upon.

عَنْ اَلنُّعْمَانِ بْنِ بَشِيرٍ ‏-رَضِيَ اَللَّهُ عَنْهُمَا‏- قَالَ: سَمِعْتُ رَسُولَ اَللَّهِ ‏- صلى الله عليه وسلم ‏-يَقُولُ‏- وَأَهْوَى اَلنُّعْمَانُ بِإِصْبَعَيْهِ إِلَى أُذُنَيْهِ: { إِنَّ اَلْحَلَالَ بَيِّنٌ, وَإِنَّ اَلْحَرَامَ بَيِّنٌ, وَبَيْنَهُمَا مُشْتَبِهَاتٌ, لَا يَعْلَمُهُنَّ كَثِيرٌ مِنْ اَلنَّاسِ, فَمَنِ اتَّقَى اَلشُّبُهَاتِ, فَقَدِ اِسْتَبْرَأَ لِدِينِهِ وَعِرْضِهِ, وَمَنْ وَقَعَ فِي اَلشُّبُهَاتِ وَقَعَ فِي اَلْحَرَامِِ, كَالرَّاعِي يَرْعَى حَوْلَ اَلْحِمَى, يُوشِكُ أَنْ يَقَعَ فِيهِ, أَلَا وَإِنَّ لِكُلِّ مَلِكٍ حِمًى, أَلَا وَإِنَّ حِمَى اَللَّهِ مَحَارِمُهُ, أَلَا وَإِنَّ فِي اَلْجَسَدِ مُضْغَةً, إِذَا صَلَحَتْ, صَلَحَ اَلْجَسَدُ كُلُّهُ, وَإِذَا فَسَدَتْ فَسَدَ اَلْجَسَدُ كُلُّهُ, أَلَا وَهِيَ اَلْقَلْبُ } مُتَّفَقٌ عَلَيْهِ.‏ (1927)‏.‏ ‏1 ‏- صحيح.‏ رواه البخاري (52)‏، ومسلم (1599)‏.‏