On the authority of Abu Muhammad al-Hasan bin Ali bin Abi Taib, the grandson of the Messenger of Allah, sallallahu alayhi wasallam, and who is dearest to him, radiyallahu anhuma, who said: I committed to memory from the Messenger of Allah, sallallahu alayhi wasallam, (the following words): Leave that about which you are in doubt for that about which you are in no doubt. [Al-Tirmidhi and al-Nasaíi related it, and al-Tirmidhi said: It is a good and genuine Hadith]