Reference: Taareekh Baghdaad – Volume 15, Page 333
al-Hifth – Ahammiyyatuhu, ‘Ajaa.ibuhu, Tareeqatuhu, Asbaabuhu – Page 19
Abu Zur’ah ar-Raazee (died 264AH) said:
My ears have never heard anything of knowledge except that it has rested upon my heart (i.e. I have memorised it).
Whilst I would walk through the market of Baghdad, I could hear the sound of female singers from the rooms, so I would put my fingers in my ears [to block out the sound], out of fear that it may rest upon my heart (i.e. I may end up memorising the words).