‏الصلاة : Hadeeth No:1698 'Abdullah reported: I prayed with the Messenger of Allaah (sallAllaahu alayhi wa sallam) and he lengthened it till I entertained an evil thought. It was said to him what that thought was. He said: I thought that I should sit down and forsake him....

‏الصلاة : Hadeeth No:1595 'A'isha reported that the Messenger of Allaah (sallAllaahu alayhi wa sallam) died (in this very state) that he observed most of his (Nafl) prayers in a sitting position....