The Book of Prayers (Kitab Al-Salat)

Muslim :: Book 4 : Hadith 1355

Abu Dharr reported: My friend (the Holy Prophet) bade me to hear and obey (the ruler) even if he is a slave having his feet and arms cut off, and observe prayer at its prescribed time. (And further said): It you find people having observed the prayer, you in fact saved your prayer, otherwise (if you join with them) that would be a Nafl prayer for you.

Source materials are from the University of Southern California MSA site
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