Narrated Abu Hurairah:
that the Messenger of Allah (ﷺ) said: "Qul Huwa Allahu Ahad is equal to a third of the Qur'an." (JA)
English reference (JA): Vol. 5, Book 42, Hadith 2899 (JA)
Arabic reference (JA): Book 45, Hadith 3145 (JA)