Sahih Al Bukhari – Book of Merits Of The Helpers In Madinah (Ansaar)

Volumn 005, Book 058, Hadith Number 208.
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Narated By Anas bin Malik RA: The people of Mecca asked Allah's Apostle PBUH to show them a miracle. So he showed them the moon split in two halves between which they saw the Hiram' mountain.