Sunan Ibn Majah 56
It was narrated that 'Abdullah bin 'Amr bin 'As said:
"I heard the Messenger of Allah (ﷺ) say: 'The affairs of the Children of Israel remained fair until Muwalladun emerged among them - the children of female slaves from other nations. They spoke of their own opinions (in religious matters) and so they went astray and led others astray.'"
حَدَّثَنَا سُوَيْدُ بْنُ سَعِيدٍ، حَدَّثَنَا ابْنُ أَبِي الرِّجَالِ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ عَمْرٍو الأَوْزَاعِيِّ، عَنْ عَبْدَةَ بْنِ أَبِي لُبَابَةَ، عَنْ عَبْدِ اللَّهِ بْنِ عَمْرِو بْنِ الْعَاصِ، قَالَ سَمِعْتُ رَسُولَ اللَّهِ ـ صلى الله عليه وسلم ـ يَقُولُ ‏
"‏ لَمْ يَزَلْ أَمْرُ بَنِي إِسْرَائِيلَ مُعْتَدِلاً حَتَّى نَشَأَ فِيهِمُ الْمُوَلَّدُونَ أَبْنَاءُ سَبَايَا الأُمَمِ فَقَالُوا بِالرَّأْىِ فَضَلُّوا وَأَضَلُّوا ‏"‏ ‏.‏