It was narrated from Abu Sa'eed Al Khudri that:A man heard another man reciting "Say: He is Allah, (the) One" and repeating it. When morning came he went to the Messenger of Allah (ﷺ) and told him about that. The Messenger of Allah (ﷺ) said: "By the One in Whose Hand is my soul, it is equal to one-third of the Quran

English translation · Sunan an-Nasa'i