Purity

Malik :: Book 2 : Hadith 2.16.65

Yahya related to me from Malik from Nafi that Salim ibn 'Abdullah said, "I was with Abdullah ibn Umar on a journey and after the sun had risen I saw him do wudu and then pray. So I said to him, 'This isn't a prayer that you normally do. 'He said, 'After I had done wudu for the subh prayer, I touched my genitals. Then I forgot to do wudu. So I did wudu again and repeated my prayer.' "

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