The Book of Prayers (Kitab Al-Salat)
Muslim :: Book 4 : Hadith 1760
Ibn 'Abbas reported that while Gabriel was sitting with the Apostle (may peace be upon him) he heard a creaking sound above him. He lifted his head and said: This As a gate opened in heaven today which had never been opened before. Then when an angel descended through it, he said: This is an angel who came down to the earth who had-never come down before. He greeted and said: Rejoice in two lights given to you which have not been given to any prophet before you: Falihat al-Kitab and the concluding verses of Suarah al-Baqara. You will never recite a letter from them for which you will not be given (a reward).