'Abdullah bin Mas'ud narrated:
"We were in a tent with the Messenger of Allah (s.a.w), about forty of us when the Messenger of Allah (s.a.w) said to us: 'Would you be pleased to be a quarter of the people of Paradise?' They said:'Yes.' He said: 'Would you be pleased to be a third of the people of Paradise?' They said: 'Yes.' He said: 'Would you be pleased to be one half of the people of Paradise? Verily none shall enter Paradise except a Muslim soul. And you are not with relation to Shirk except like the white hair on the hide of a black bull or like the black hair on the hide of a red bull." (PT)
English reference (PT): Vol. 4, Book 12, Hadith 2547 (PT)
Arabic reference (PT): Book 38, Hadith 2744 (PT)