What is the ruling on lowering the hands in prayer?
Lowering the hands in prayer is against the Sunnah. The Sunnah for the worshipper is to place the right hand on the left hand, and it has been authentically reported in Sahih Al-Bukhari in the Hadith of Sahl bin Saad that he said: The people were ordered to place the right hand over the left forearm in prayer.  And this is a general order, unless he stops it in order to bow, which requires him to place his hands on his knees, or prostrate, in which the hands are on the floor, or the sitting, in which his hands are on his thighs. But as long as he remains standing, the right hand should be on the left forearm before bowing and after bowing.
 Al-Bukhari no. 740.
Shaykh Muhammad bin Saalih al-`Uthaymeen
Fatawa Islamiyah Vol. 2 Page 237