When the Messenger of Allah ﷺ lay down to sleep, he would place his right hand under his right cheek. He used his right hand for eating, for purification, for prayer, and for his clothing, and he used his left hand for everything else. He used to fast on Mondays and Thursdays.
حدثنا حسين بن علي عن زائدة عن عاصم عن المسيب
كان رسول الله ﷺ إذا أخذ مضجعه وضع يده اليمنى تحت خده الأيمن وكانت يمينه لطعامه وطهوره وصلاته وثيابه وكانت شماله لما سوى ذلك وكان يصوم الاثنين والخميس