Anas said a man told God's messenger that he liked the sūra “Say, He is God, One,” to which he replied, “Your love of it will bring you into paradise.”
Tirmidhī transmitted it and Bukhārī transmitted something to the same effect.
‘Ā’isha said that the Prophet sent a man in charge of an expedition and he would recite for his companions during their prayer, finishing with “Say, He is God, One.” When they returned they mentioned that to the Prophet, and he told them to ask him why he did that. They asked him and he replied, “Because it is a description of the Compassionate One, and I like to recite it.” Then the Prophet said, “Tell him that God loves him.”
‘Uqba b. ‘Āmir reported God’s messenger as saying, “What wonderful verses have been sent down to-night! The like of them has never been seen. They are ‘Say, I seek refuge in the Lord of the dawn’ and ‘Say, I seek refuge in the Lord of men.’” (Qur’ān, 113 and 114).
He reported God’s messenger as saying, “Is any of you incapable of reciting a third of the Qur’ān in a night?” On being asked how they could recite a third of the Qur’ān he replied. “‘Say, He is God, One’ (Qur’ān, 112) is equivalent to a third of the Qur’ān.”
Muslim transmitted it, and Bukhārī transmitted it from Abū Sa'īd.