Sunan ad-Darimi

Muhammad bin Hasan bin Ali said: We asked our master Jabir bin Abdullah, may Allah be pleased with them both, during the time of Hajjaj, who used to delay the prayer. Our master Jabir, may Allah be pleased with him, said: The Prophet Muhammad, peace and blessings be upon him, used to perform the Zuhr prayer when the sun had declined, and the Asr prayer (he would perform) when the sun was still clear, and the Maghrib prayer he would perform when the sun had set, and the Isha prayer he would sometimes perform early and sometimes late; when the people gathered early, he would perform it early, and when the people delayed, he would delay the prayer. And the Fajr prayer, all of them (or he said) or the Prophet Muhammad, peace and blessings be upon him, would perform it in darkness.