Hadith 389

Sahih Bukhari

Book 65: Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))

Chapter 1

What has been said about Fãtihat al-Kitab (i.e., the Opening of the Book)

باب مَا جَاءَ فِي فَاتِحَةِ الْكِتَابِ

It is also called Umm-ul-Kitab (i.e., the Mother of the Book), because it is the first Surah that has been written in the copies of the Quran, and it is also the first Surah to be recited in Salat (prayer).
وَسُمِّيَتْ أُمَّ الْكِتَابِ أَنَّهُ يُبْدَأُ بِكِتَابَتِهَا فِي الْمَصَاحِفِ، وَيُبْدَأُ بِقِرَاءَتِهَا فِي الصَّلاَةِ. وَالدِّينُ الْجَزَاءُ فِي الْخَيْرِ وَالشَّرِّ، كَمَا تَدِينُ تُدَانُ. وَقَالَ مُجَاهِدٌ: بِالدِّينِ بِالْحِسَابِ. {مَدِينِينَ} مُحَاسَبِينَ.
Sahih al-Bukhari 4868
حَدَّثَنَا مُسَدَّدٌ، حَدَّثَنَا يَحْيَى، عَنْ شُعْبَةَ، عَنْ قَتَادَةَ، عَنْ أَنَسٍ، قَالَ انْشَقَّ الْقَمَرُ فِرْقَتَيْنِ‏.‏
Anas:

The moon was cleft asunder into two parts.