The Book of Prayers (Kitab Al-Salat)

Muslim :: Book 4 : Hadith 1092

Mus'ab b. Sa'd b. Abu Waqqas reported: I said prayer by the side of my father. When I bowed I intertwined my fingers and placed them between my knees. He struck my hands. When he completed the prayer he said: We used to do that but then were commanded to lift (our palms) to the knees.

Source materials are from the University of Southern California MSA site
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