Purification (Kitab Al-Taharah)

Dawud :: Book 1 : Hadith 162

Narrated Ali ibn AbuTalib:

If the religion were based on opinion, it would be more important to wipe the under part of the shoe than the upper but I have seen the Messenger of Allah (peace_be_upon_him) wiping over the upper part of his shoes.

Source materials are from the University of Southern California MSA site
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