It wasnarrated that Mus'ab bin Sa'd said:
"I bowed (in prayer)besidemy father, and I put my hands between my knees. He struck myhand andsaid: 'We used to do that, then we were commanded to put themonthe knees.'" (JA)
English reference (JA): Vol. 1, Book 5, Hadith 873 (JA)
Arabic reference (JA): Book 5, Hadith 922 (JA)