Sahih Bukhari Volume 006, Book 060, Hadith Number 375.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 60. Prophetic Commentary on the Qur'an (Tafseer of The Prophet (PBUH))
Narrated By Mujahid : Ibn Abbas said, "Allah ordered His Prophet to celebrate Allah's praises after all prayers." He refers to His Statement: 'After the prayers.' (50.40)