Bukhari Volumn 007, Book 071, Hadith Number 606.
Narated By Ibn 'Abbas :Allah's Apostle said, 'Nations were displayed before me; one or two prophets would pass by along with a few followers. A prophet would pass by accompanied by nobody. Then a big crowd of people passed in front of me and I asked, Who are they Are they my followers?" It was said, 'No. It is Moses and his followers It was said to me, 'Look at the horizon.'' Behold! There was a multitude of people filling the horizon. Then it was said to me, 'Look there and there about the stretching sky! Behold! There was a multitude filling the horizon,' It was said to me, 'This is your nation out of whom seventy thousand shall enter Paradise without reckoning.' "Then the Prophet entered his house without telling his companions who they (the 70,000) were. So the people started talking about the issue and said, "It is we who have believed in Allah and followed His Apostle; therefore those people are either ourselves or our children who are born in the Islamic era, for we were born in the Pre-Islamic Period of Ignorance.'' When the Prophet heard of that, he came out and said. "Those people are those who do not treat themselves with Ruqya, nor do they believe in bad or good omen (from birds etc.) nor do they get themselves branded (Cauterised). but they put their trust (only) in their Rabb" On that 'Ukasha bin Muhsin said. "Am I one of them, O Allah's Apostle?' The Prophet said, "Yes." Then another person got up and said, "Am I one of them?" The Prophet said, 'Ukasha has anticipated you."