Sayyiduna al-Bara' (may Allah be pleased with him) says: (Allah Almighty says:) "Say: In the bounty of Allah and in His mercy, in that let them rejoice; it is better than all that they gather." Sayyiduna al-Bara' (may Allah be pleased with him) says: Here the bounty of Allah means the Qur'an, and His mercy means that Allah Almighty has made you people of the Qur'an (that is, has made you believers in the Qur'an).
Imam al-Tabarani recorded it in al-Mu'jam al-Awsat. Its chain contains a narrator, Atiyyah al-Awfi, and he is da'if (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب التفسير / 11066