Sahih Muslim 50 a
It is narrated on the authority 'Abdullah b. Mas'ud that the Messenger of Allah (may peace and blessings be upon him) observed:
Never a Prophet had been sent before me by Allah towards his nation who had not among his people (his) disciples and companions who followed his ways and obeyed his command. Then there came after them their successors who said whatever they did not practise, and practised whatever they were not commanded to do. He who strove against them with his hand was a believer: he who strove against them with his tongue was a believer, and he who strove against them with his heart was a believer and beyond that there is no faith even to the extent of a mustard seed. Abu Rafi' said: I narrated this hadith to 'Abdullah b. 'Umar; he contradicted me. There happened to come 'Abdullah b. Mas'ud who stayed at Qanat, and 'Abdullah b 'Umar wanted me to accompany him for visiting him (as 'Abdullah b. Mas'ud was ailing), so I went along with him and as we sat (before him) I asked Ibn Mas'ud about this hadith. He narrated it in the same way as I narrated it to Ibn 'Umar.
حَدَّثَنِي عَمْرٌو النَّاقِدُ، وَأَبُو بَكْرِ بْنُ النَّضْرِ وَعَبْدُ بْنُ حُمَيْدٍ - وَاللَّفْظُ لِعَبْدٍ - قَالُوا حَدَّثَنَا يَعْقُوبُ بْنُ إِبْرَاهِيمَ بْنِ سَعْدٍ، قَالَ حَدَّثَنِي أَبِي، عَنْ صَالِحِ بْنِ كَيْسَانَ، عَنِ الْحَارِثِ، عَنْ جَعْفَرِ بْنِ عَبْدِ اللَّهِ بْنِ الْحَكَمِ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ الْمِسْوَرِ، عَنْ أَبِي رَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ مَسْعُودٍ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏
"‏ مَا مِنْ نَبِيٍّ بَعَثَهُ اللَّهُ فِي أُمَّةٍ قَبْلِي إِلاَّ كَانَ لَهُ مِنْ أُمَّتِهِ حَوَارِيُّونَ وَأَصْحَابٌ يَأْخُذُونَ بِسُنَّتِهِ وَيَقْتَدُونَ بِأَمْرِهِ ثُمَّ إِنَّهَا تَخْلُفُ مِنْ بَعْدِهِمْ خُلُوفٌ يَقُولُونَ مَا لاَ يَفْعَلُونَ وَيَفْعَلُونَ مَا لاَ يُؤْمَرُونَ فَمَنْ جَاهَدَهُمْ بِيَدِهِ فَهُوَ مُؤْمِنٌ وَمَنْ جَاهَدَهُمْ بِلِسَانِهِ فَهُوَ مُؤْمِنٌ وَمَنْ جَاهَدَهُمْ بِقَلْبِهِ فَهُوَ مُؤْمِنٌ وَلَيْسَ وَرَاءَ ذَلِكَ مِنَ الإِيمَانِ حَبَّةُ خَرْدَلٍ ‏"‏ ‏.‏ قَالَ أَبُو رَافِعٍ فَحَدَّثْتُهُ عَبْدَ اللَّهِ بْنَ عُمَرَ فَأَنْكَرَهُ عَلَىَّ فَقَدِمَ ابْنُ مَسْعُودٍ فَنَزَلَ بِقَنَاةَ فَاسْتَتْبَعَنِي إِلَيْهِ عَبْدُ اللَّهِ بْنُ عُمَرَ يَعُودُهُ فَانْطَلَقْتُ مَعَهُ فَلَمَّا جَلَسْنَا سَأَلْتُ ابْنَ مَسْعُودٍ عَنْ هَذَا الْحَدِيثِ فَحَدَّثَنِيهِ كَمَا حَدَّثْتُهُ ابْنَ عُمَرَ ‏.‏ قَالَ صَالِحٌ وَقَدْ تُحُدِّثَ بِنَحْوِ ذَلِكَ عَنْ أَبِي رَافِعٍ ‏.‏