Ibn Hibban

Sayyiduna Abu Dharr Ghifari (may Allah be pleased with him) narrates: We observed the fasts of Ramadan with the Prophet (peace and blessings of Allah be upon him). He did not lead us in voluntary prayers on the sixth night. He led us in voluntary prayers on the fifth night until he began to wait for the night. We said: O Messenger of Allah (peace and blessings of Allah be upon him), if you would lead us in voluntary prayers on the remaining nights, (it would be appropriate). The Prophet (peace and blessings of Allah be upon him) said: Whoever prays with the Imam until he finishes, he will have the reward of praying the entire night. Then the Prophet (peace and blessings of Allah be upon him) did not lead us in prayer until three nights remained in the month, so he led us in prayer on the third night. He gathered his family and his wives as well, and he led us in voluntary prayers until we feared that we would miss success. The narrator says: I asked: What is meant by "success"? He replied: Suhoor (pre-dawn meal). (Imam Ibn Hibban, may Allah have mercy on him, says: The statement of Sayyiduna Abu Dharr Ghifari (may Allah be pleased with him) that he did not lead us in voluntary prayers on the sixth night, and he led us in voluntary prayers on the fifth night, means the sixth or fifth night of the remaining ten nights. It does not mean the fifth or sixth night of the month that had already passed, because the month in which the Prophet (peace and blessings of Allah be upon him) addressed his Ummah had twenty-nine days. So the sixth night of the remaining part of a twenty-nine-day month was the twenty-fourth night, and the fifth night of the remaining part of a twenty-nine-day month would be the twenty-fifth night.)