I heard Messenger of Allah (may peace be upon himn) as having said this (and Nu'man) pointed towards his ears with his fingers): What is lawful is evident and what is unlawful is evident, and in between them are the things doubtful which many people do not know. So he who guards against doubtful things keeps his religion and honour blameless, and he who indulges in doubtful things indulges in fact in unlawful things, just as a shepherd who pastures his animals round a preserve will soon pasture them in it. Beware, every king has a preserve, and the things God his declaced unlawful are His preserves. Beware, in the body there is a piece of flesh; if it is sound, the whole body is sound and if it is corrupt the whole body is corrupt, and hearken it is the heart.  

سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ، وَأَهْوَى النُّعْمَانُ بِإِصْبَعَيْهِ إِلَى أُذُنَيْهِ: «إِنَّ الْحَلاَلَ بَيِّنٌ وَإِنَّ الْحَرَامَ بَيِّنٌ، وَبَيْنَهُمَا مُشْتَبِهَاتٌ لاَ يَعْلَمُهُنَّ كَثِيرٌ مِنَ النَّاسِ۔ فَمَنِ اتَّقَى الشُّبُهَاتِ اسْتَبْرَأَ لِدِينِهِ وَعِرْضِهِ، وَمَنْ وَقَعَ فِي الشُّبُهَاتِ وَقَعَ فِي الْحَرَامِ كَالرَّاعِي يَرْعَى حَوْلَ الْحِمَى يُوشِكُ أَنْ يَرْتَعَ فِيهِ۔ أَلاَ وَإِنَّ لِكُلِّ مَلِكٍ حِمًى۔ أَلاَ وَإِنَّ حِمَى اللَّهِ مَحَارِمُهُ۔ أَلاَ وَإِنَّ فِي الْجَسَدِ مُضْغَةً إِذَا صَلَحَتْ صَلَحَ الْجَسَدُ كُلُّهُ، وَإِذَا فَسَدَتْ فَسَدَ الْجَسَدُ كُلُّهُ۔ أَلاَ وَهِيَ الْقَلْبُ۔»  

I heard Messenger of Allah ﷺ saying, 'Both legal and illegal things are evident but in between them there are doubtful (suspicious) things and most of the people have no knowledge about them. So whoever saves himself from these suspicious things saves his religion and his honor. And whoever indulges in these suspicious things is like a shepherd who grazes (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 His illegal (forbidden) things. Beware! There is a piece of flesh in the body if it becomes good (reformed) the whole body becomes good but if it gets spoilt the whole body gets spoilt and that is the heart.  

سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ الْحَلاَلُ بَيِّنٌ وَالْحَرَامُ بَيِّنٌ وَبَيْنَهُمَا مُشَبَّهَاتٌ لاَ يَعْلَمُهَا كَثِيرٌ مِنَ النَّاسِ فَمَنِ اتَّقَى الْمُشَبَّهَاتِ اسْتَبْرَأَ لِدِيِنِهِ وَعِرْضِهِ وَمَنْ وَقَعَ فِي الشُّبُهَاتِ كَرَاعٍ يَرْعَى حَوْلَ الْحِمَى يُوشِكُ أَنْ يُوَاقِعَهُ أَلاَ وَإِنَّ لِكُلِّ مَلِكٍ حِمًى أَلاَ إِنَّ حِمَى اللَّهِ فِي أَرْضِهِ مَحَارِمُهُ أَلاَ وَإِنَّ فِي الْجَسَدِ مُضْغَةً إِذَا صَلَحَتْ صَلَحَ الْجَسَدُ كُلُّهُ وَإِذَا فَسَدَتْ فَسَدَ الْجَسَدُ كُلُّهُ أَلاَ وَهِيَ الْقَلْبُ