The Book of Purification
1/23. Chapter:
The Prohibition Of Touching One's Penis With the Right Hand When Relieving Oneself
Sunan an-Nasai
أَخْبَرَنَا يَحْيَى بْنُ دُرُسْتَ، قَالَ أَنْبَأَنَا أَبُو إِسْمَاعِيلَ، - وَهُوَ الْقَنَّادُ - قَالَ حَدَّثَنِي يَحْيَى بْنُ أَبِي كَثِيرٍ، أَنَّ عَبْدَ اللَّهِ بْنَ أَبِي قَتَادَةَ، حَدَّثَهُ عَنْ أَبِيهِ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ " إِذَا بَالَ أَحَدُكُمْ فَلاَ يَأْخُذْ ذَكَرَهُ بِيَمِينِهِ " .
It was narrated from 'Abdullah bin Abi Qatadah, from his father, that the Messenger of Allah (ﷺ said: "When any one of you urinates, let him not hold his penis in his right hand."
Reference : Sunan an-Nasa'i 24In-book reference : Book 1, Hadith 24English translation : Vol. 1, Book 1, Hadith 24