Musnad Ahmad 31:612

Rawh narrated to us, Sa'id narrated to us, from Qatadah, from Abu al-Mutawakkil al-Naji, from Abu Sa'id al-Khudri, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "The believers will be saved from the Fire on the Day of Resurrection, and they will be detained upon a bridge between Paradise and the Fire. Retribution will be taken for some of them against others for injustices that existed between them in the world. Until, when they have been refined and purified, they will be granted permission to enter Paradise. By the One in Whose hand is my soul, one of them will be more guided to his dwelling in Paradise than he was to his dwelling that he had in the world."