Abdullah bin Abbas (may Allah be pleased with them both) narrates: "Once, Gabriel was sitting with the Prophet Muhammad (peace be upon him). During this, he heard the sound of a door opening above (in the sky). He raised his head and said: Today, such a door of the sky has opened which has never opened before. Then an angel came to them and said to the Prophet Muhammad (peace be upon him): Accept the glad tidings of two such Surahs which have not been given to any prophet before you; they are Surah Al-Fatihah and the last verses of Surah Al-Baqarah. Whatever letter of them you recite, you will be granted that thing."
Hadith Referenceصحیح ابن حبان / كتاب الرقائق / 778
Hadith Gradingفضيلة الشيخ الإمام محمد ناصر الدين الألبانيصحيح: مفضيلة الشيخ العلّامة شُعيب الأرناؤوطإسناده صحيح على شرط مسلم، معاوية بن هشام وإن كان فيه كلام ينزل فيه عن رتبة الصحة، قد توبع عليه، وباقي رجاله ثقات.