Narrated Al-Nu'man b. Bashir: I heard Messenger of Allah (ﷺ) say: But between them are certain doubtful things which many people do not recognize. He who guards against doubtful things keeps his religion and his honor blameless, but he who falls into doubtful things falls into what is unlawful.
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا إِبْرَاهِيمُ بْنُ مُوسَى الرَّازِيُّ، أَخْبَرَنَا عِيسَى، حَدَّثَنَا زَكَرِيَّا، عَنْ عَامِرٍ الشَّعْبِيِّ، قَالَ سَمِعْتُ النُّعْمَانَ بْنَ بَشِيرٍ، قَالَ سَمِعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ بِهَذَا الْحَدِيثِ قَالَ " وَبَيْنَهُمَا مُشَبَّهَاتٌ لا يَعْلَمُهَا كَثِيرٌ مِنَ النَّاسِ فَمَنِ اتَّقَى الشُّبُهَاتِ اسْتَبْرَأَ عِرْضَهُ وَدِينَهُ وَمَنْ وَقَعَ فِي الشُّبُهَاتِ وَقَعَ فِي الْحَرَامِ " .
sunnah.com