وَحَدَّثَنِي عَنْ مَالِكٍ، قَالَ بَلَغَنِي عَنْ نَافِعٍ، أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ، كَانَ يَرَى ابْنَهُ عُبَيْدَ اللَّهِ بْنَ عَبْدِ اللَّهِ يَتَنَفَّلُ فِي السَّفَرِ فَلاَ يُنْكِرُ عَلَيْهِ ‏.‏

Yahya related to me that Malik said, "I have heard from Nafi thatAbdullah ibn Umar used to see his son, Ubaydullah ibn Abdullah, doingvoluntary prayers on a journey,and he would not disapprove of it." Translation Not Available

Book Ref: Muwatta Imam Malik Book 9 Hadith 355
Web Ref:  Muwatta Imam Malik Book 9 Hadith 26

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