Sunan At-Tirmidhi

Narrated Ibn 'Abbas:that the Messenger of Allah (ﷺ) said: ""Idha Zulzilat is equal to half of the Qur'an, Qul Huwa Allahu Ahad is equal to a third of the Qur'an, and Yul Ya Ayyuhal-Kafirun is equal to a fourth of the Qur'an