Hadith 1790
Sayyiduna Abdullah bin Amr (may Allah be pleased with them both) narrated in a marfu’ (attributed to the Prophet) tradition that the most beloved fast to Allah is the fast of Dawud (peace be upon him); he would fast one day and break the fast the next day. And the most beloved prayer to Allah (of the night prayers) is the prayer of Dawud (peace be upon him); he would pray for half the night, sleep for one third, and recite tasbih for one sixth of the night. Imam Darimi (may Allah have mercy on him) said: This last sentence is incorrect; the correct version is that he would sleep for half the night, pray for one third, and recite tasbih for one sixth.