Musnad Ahmad 30:3075

Waki’ narrated to us, from ‘Ali ibn Mubarak, from Yahya ibn Abi Kathir, from ‘Amir al-‘Uqayli, from his father, from Abu Hurayrah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Verily, I know the first three who will enter Paradise: the martyr, a slave who fulfilled the right of Allah and the right of his masters, and a poor person who is chaste and abstinent. And verily, I know the first three who will enter the Fire: an overpowering ruler, a possessor of wealth who does not fulfill its right, and a boastful poor person."