Waliuddin Abu Abdullah Mahmud Tabrizi, Selections from Muḥammadan Traditions…
“ Then ʿOmar said, "O Apostle of God, how is it with the man who fasts the whole of the time?" The Apostle of God replied, "There is (for him) neither fast nor breaking of fast," or he said, "He has neither fasted nor broken the fast." ʿOmar said, "How is it with the man who fasts two days, and breaks the fast one day?" He replied, "Is anyone able to do that?" He said, "How is it with the man who fasts one day, and breaks the fast one day?" He replied, "That was the fast of David." He said, "How is it with the man who fasts one day, and abstains from fasting two days?" ”
