Sayyiduna Umar bin Khattab (may Allah be pleased with him) narrates that when the Messenger of Allah (peace and blessings of Allah be upon him) separated himself from his wives, I said, "O Messenger of Allah, you have stayed in the upper room for twenty-nine days (while you had chosen separation for a month)." So the Messenger of Allah (peace and blessings of Allah be upon him) said: "Indeed, a month can also be of twenty-nine days."