Imam al-Dhahabi reports in al-Siyar (12/494):
‘Amr bin Tamim al-Makki said: I heard Muhammad bin Isma’il al-Tirmidhi [who] said: I heard al-Muzanee saying,
“The Tawhid of any [person] is not valid, sound until he knows that Allaah the Exalted is over His Throne, with His attributes.” I said to him, “Like what?” He said, “Hearing, seeing, knowing.”