Silsilat al-Ahadith al-Sahihah

Sayyiduna Abu Hurairah (may Allah be pleased with him) reports that the Messenger of Allah (peace and blessings be upon him) said: "Gather together, for I am going to recite to you one third of the Qur'an." Those who were to gather, gathered. The Prophet (peace and blessings be upon him) came and recited «قُلْ هُوَ اللَّهُ أَحَدٌ» and then went back. We began to say to one another: It seems that some (new) news has come from the sky which has made the Prophet (peace and blessings be upon him) enter his house. Then the Noble Prophet (peace and blessings be upon him) came out and said: "I told you that I would recite to you one third of the Qur'an. Be aware! (Surah Al-Ikhlas) is equal to one third of the Qur'an (which I have recited to you)."