Sayyiduna Abu Sa'id Khudri (may Allah be pleased with him) narrated that the Messenger of Allah (peace and blessings be upon him) led us in the 'Asr prayer during the day, then delivered a sermon to us until the sun set. He (peace and blessings be upon him) did not leave anything unmentioned that was to happen until the Day of Resurrection, except that he explained it to us. Whoever remembered it, remembered it, and whoever forgot it, forgot it. And when the sun was about to set, he (peace and blessings be upon him) said: "And the amount of your world that has passed and the amount that remains is like this day of yours: what has passed of it and what remains of it."