Musnad Ahmad 54:1

'Abd al-Razzaq and Rawh narrated to us, they said: Ibn Jurayj narrated to us, he said: Hasan ibn Muslim informed me, from Tawus, from a man who had met the Prophet, may Allah bless him and grant him peace, that the Prophet, may Allah bless him and grant him peace, said: "Tawaf is only a prayer, so when you perform Tawaf, speak little." 'Abdullah said: My father said: Muhammad did not attribute it to the Prophet (marfu').