It is narrated from Sayyiduna Zaid bin Khalid Al-Juhani, may Allah be pleased with him, that he said: I will certainly observe the night prayer of the Messenger of Allah, peace and blessings be upon him. Sayyiduna Zaid, may Allah be pleased with him, says: I leaned against the threshold of his house, or the house which was covered with hair. Then the Messenger of Allah, peace and blessings be upon him, stood up and prayed two rak'ahs, very long, very long, very long. Then he prayed two rak'ahs, somewhat shorter than those, then he prayed two rak'ahs, somewhat shorter than those, then he prayed two rak'ahs, somewhat shorter than those, then he prayed two rak'ahs, somewhat shorter than those, then he prayed two rak'ahs, somewhat shorter than those, then he prayed two rak'ahs, somewhat shorter than those, then he prayed one rak'ah as witr. Altogether, he prayed thirteen rak'ahs.