Sunan an-Nasa'i 194
سنن النسائي#194Sahihأَخْبَرَنَا عُبَيْدُ اللَّهِ بْنُ سَعِيدٍ، قَالَ أَنْبَأَنَا عَبْدُ الرَّحْمَنِ، عَنْ زَائِدَةَ، ح وَأَخْبَرَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، - وَاللَّفْظُ لَهُ - أَنْبَأَنَا أَبُو الْوَلِيدِ، حَدَّثَنَا زَائِدَةُ، عَنِ الرُّكَيْنِ بْنِ الرَّبِيعِ بْنِ عَمِيلَةَ الْفَزَارِيِّ، عَنْ حُصَيْنِ بْنِ قَبِيصَةَ، عَنْ عَلِيٍّ، - رضى الله عنه - قَالَ كُنْتُ رَجُلاً مَذَّاءً فَسَأَلْتُ النَّبِيَّ صلى الله عليه وسلم فَقَالَ " إِذَا رَأَيْتَ الْمَذْىَ فَتَوَضَّأْ وَاغْسِلْ ذَكَرَكَ وَإِذَا رَأَيْتَ فَضْخَ الْمَاءِ فَاغْتَسِلْ " .
It was narrated that 'Ali said:"I was one who had a lot of prostatic discharge, so I asked the Prophet (ﷺ) and he said: 'If you see Madhi (prostatic fluid) then perform Wudu' and wash your penis, but if you see semen ejaculated, then perform Ghusl
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
In-book reference: 1:195