Abu Dawud
Prayer
Book Number: 002 / Hadith Number: 1288
Narated By 'Aisha, wife of the Prophet (pbuh) : The Apostle of Allah (pbuh) never offered prayer in the forenoon, but I offered it. The Apostle of Allah (pbuh) would give up an action though he liked to do it, lest the people should continue it and it is prescribed for them.