Sunan an-Nasa'i, Volume 6, Book 47, Hadith 5013 (DarusSalam) ⓘ
It was narrated that Abu Sa'eed Al-Khudri said: "The Messenger of Allah [SAW] said: 'No one of you disputes more intensely for something that is rightly his in this world, than the believers will dispute with their Lord for their brothers who have entered the Fire. They will say: 'Our Lord, our brothers used to pray with us and fast with us, and perform Hajj with us, and you have caused them to enter the Fire?' He will say: 'Go and bring forth whomever you recognize among them.' So they will go to them, and will recognize them by their appearances. Among them will be those who have been seized by the Fire up to the middle of their shins, and some among them those whom it has taken up to his ankles. They will bring them forth, then they will say: 'Our Lord, we have brought forth those whom You commanded us (to bring forth).' He will say: 'Bring forth everyone in whose heart is faith the weight of a Dinar.' Then He will say: 'Everyone in whose heart is faith the weight of half a Dinar,' until He will say: 'In whose heart is faith the weight of the smallest speck.'" Abu Sa'eed said: "Whoever does not believe this, let him read the Verse: 'Verily, Allah forgives not that partners should be set up with Him (in worship), but He forgives except that (anything else) to whom He wills up to a tremendous (sin).'"
أَخْبَرَنَا مُحَمَّدُ بْنُ رَافِعٍ قَالَ حَدَّثَنَا عَبْدُ الرَّزَّاقِ قَالَ أَنْبَأَنَا مَعْمَرٌ عَنْ زَيْدِ بْنِ أَسْلَمَ عَنْ عَطَاءِ بْنِ يَسَارٍ عَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ قَالَ قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ مَا مُجَادَلَةُ أَحَدِكُمْ فِي الْحَقِّ يَكُونُ لَهُ فِي الدُّنْيَا بِأَشَدَّ مُجَادَلَةً مِنْ الْمُؤْمِنِينَ لِرَبِّهِمْ فِي إِخْوَانِهِمْ الَّذِينَ أُدْخِلُوا النَّارَ قَالَ يَقُولُونَ رَبَّنَا إِخْوَانُنَا كَانُوا يُصَلُّونَ مَعَنَا وَيَصُومُونَ مَعَنَا وَيَحُجُّونَ مَعَنَا فَأَدْخَلْتَهُمْ النَّارَ قَالَ فَيَقُولُ اذْهَبُوا فَأَخْرِجُوا مَنْ عَرَفْتُمْ مِنْهُمْ قَالَ فَيَأْتُونَهُمْ فَيَعْرِفُونَهُمْ بِصُوَرِهِمْ فَمِنْهُمْ مَنْ أَخَذَتْهُ النَّارُ إِلَى أَنْصَافِ سَاقَيْهِ وَمِنْهُمْ مَنْ أَخَذَتْهُ إِلَى كَعْبَيْهِ فَيُخْرِجُونَهُمْ فَيَقُولُونَ رَبَّنَا قَدْ أَخْرَجْنَا مَنْ أَمَرْتَنَا قَالَ وَيَقُولُ أَخْرِجُوا مَنْ كَانَ فِي قَلْبِهِ وَزْنُ دِينَارٍ مِنْ الْإِيمَانِ ثُمَّ قَالَ مَنْ كَانَ فِي قَلْبِهِ وَزْنُ نِصْفِ دِينَارٍ حَتَّى يَقُولَ مَنْ كَانَ فِي قَلْبِهِ وَزْنُ ذَرَّةٍ قَالَ أَبُو سَعِيدٍ فَمَنْ لَمْ يُصَدِّقْ فَلْيَقْرَأْ هَذِهِ الْآيَةَ إِنَّ اللَّهَ لَا يَغْفِرُ أَنْ يُشْرَكَ بِهِ وَيَغْفِرُ مَا دُونَ ذَلِكَ لِمَنْ يَشَاءُ إِلَى عَظِيمًا
also referenced under: Hadith 5010 (Reference) & Book 47, Hadith 26 (In-Book)