حَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، وَمُحَمَّدُ بْنُ بَشَّارٍ، - وَاللَّفْظُ لاِبْنِ الْمُثَنَّى - قَالاَ حَدَّثَنَا مُحَمَّدُ بْنُ جَعْفَرٍ، حَدَّثَنَا شُعْبَةُ، عَنْ أَبِي إِسْحَاقَ، عَنْ عَمْرِو بْنِ مَيْمُونٍ، عَنْ عَبْدِ اللَّهِ، قَالَ كُنَّا مَعَ رَسُولِ اللَّهِ صلى الله عليه وسلم فِي قُبَّةٍ نَحْوًا مِنْ أَرْبَعِينَ رَجُلاً فَقَالَ ‏"‏ أَتَرْضَوْنَ أَنْ تَكُونُوا رُبُعَ أَهْلِ الْجَنَّةِ قَالَ قُلْنَا نَعَمْ ‏.‏ فَقَالَ ‏"‏ أَتَرْضَوْنَ أَنْ تَكُونُوا ثُلُثَ أَهْلِ الْجَنَّةِ ‏"‏ فَقُلْنَا نَعَمْ ‏.‏ فَقَالَ ‏"‏ وَالَّذِي نَفْسِي بِيَدِهِ إِنِّي لأَرْجُو أَنْ تَكُونُوا نِصْفَ أَهْلِ الْجَنَّةِ وَذَاكَ أَنَّ الْجَنَّةَ لاَ يَدْخُلُهَا إِلاَّ نَفْسٌ مُسْلِمَةٌ وَمَا أَنْتُمْ فِي أَهْلِ الشِّرْكِ إِلاَّ كَالشَّعْرَةِ الْبَيْضَاءِ فِي جِلْدِ الثَّوْرِ الأَسْوَدِ أَوْ كَالشَّعْرَةِ السَّوْدَاءِ فِي جِلْدِ الثَّوْرِ الأَحْمَرِ ‏"‏ ‏.‏

'Abdullah (b. Mas'ud) reported: We, about forty men, were with the Messenger of Allah (PBUH) in a camp when he said: Aren't you pleased that they should constitute one-fourth of the inhabitants of Paradise? He (the narrator) said: Yes. He (the Holy Prophet) again said: Aren't you pleased that you should constitute one-third of the inhabitants of Paradise? They said: Yes. Upon this he again said: By Him in Whose Hand is my life, I hope that you would constitute one-half of the inhabitants of Paradise and the reason is that no one would be admitted into Paradise but a believer and you are no more among the polytheists than as a white hair on the skin of a black ox or a black hair on the skin of a red ox. Translation Not Available

Book Ref: Sahih Muslim Book 1 Hadith 428
Web Ref:  Sahih Muslim Book 1 Hadith 221 b