Hadith: Q4978, Chapter. How the Divine Revelation used to be revealed and what was the first thing revealed (to the Messenger )., Sahih Bukhari

صحيح البخاري

Sahih Bukhari

كتاب فضائل القرآن

The Book of The Virtues of The Quran

باب كيف نزول الوحي وأول ما نزل:

Chapter. How the Divine Revelation used to be revealed and what was the first thing revealed (to the Messenger).