"The Prophet said (Allah bless him and give him peace): 'If one of you gets up during the night, let him begin his ritual prayer with two abbreviated cycles.'”
"If the Prophet (Allah bless him and give him peace) did not perform the ritual prayer during the night, because sleep had prevented him, or his eyes had been too weary, during the daytime, he would perform twelve cycles of ritual prayer during the daytime.”
“Determined to contemplate the ritual prayer of the Prophet (Allah bless him and give him peace) intently, for I laid my head on his doorstep or his hair tent. Allah’s Messenger (Allah bless him and give him peace) then performed two brisk cycles of ritual prayer. After this he performed two long, long, long cycles. Then he performed two cycles that were shorter than the two before them. Then he performed two cycles that were shorter than the two that were before them. Then he performed two cycles that were shorter than the two that preceded them. Then he performed two cycles that were shorter than the two that were before them. Finally he performed a single-numbered cycle, which added up to a total of thirteen cycles.”
