The Book of Prayers (Kitab Al-Salat)

Muslim :: Book 4 : Hadith 1354

Abu Dharr reported: The Messenger of Allah (may peace be upon him) said to me: O Abu Dharr, you would soon find after me rulers who would make their prayers dead. You should say prayer at its prescribed time. If you say prayer at its prescribed time that would be a supererogatory prayer for you, otherwise you saved your prayer.

Source materials are from the University of Southern California MSA site
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