DOES TOUCHING THE PRIVATE PART INVALIDATE WUDOO’?
Touching the private part without a barrier invalidates wudoo’ according to many scholars among the Sahaabah and those who came after them of the Taabi‘een and the imams, including Maalik, al-Shaafa‘i and Ahmad. They quoted as evidence for that several hadeeths, such as
Narrated Busrah daughter of Safwan:Abdullah ibn AbuBakr reported that he heard Urwah say: I entered upon Marwan ibn al-Hakam. We mentioned things that render the ablution void. Marwan said: Does it become void by touching the penis? Urwah replied: This I do not know. Marwan said: Busrah daughter of Safwan reported to me that she heard the Messenger of Allah (p.b.u.h) say: He who touches his penis should perform ablution.
ABU DAWOOD (Book 1, Hadith 181)
AL-MARDAAWI SAID :-
The apparent meaning of his words, “touching the private part with his hand”, is that the touching occurs without a barrier, and this is the correct view.
IBN ‘UTHAYMEEN SAID :-
if there is a barrier, it is not regarded as touching.
(AL-SHARH AL-MUMTI‘ 1/228)
Others were of the view that touching the private part does not invalidate wudoo’, as is the view of Abu Haneefah. Some of the scholars differentiated between touching the private part with desire and without desire. Wudoo’ is invalidated if it is touched with desire, and it is not invalidated if it is without desire. This is a very strong opinion and was regarded as such by Shaykh Ibn ‘Uthaymeen in al-Sharh al-Mumti‘. He stated clearly that he regarded it as more correct in his commentary on Buloogh al-Maraam.
To sum up: if a person touches his private part, it is mustahabb for him to do wudoo’ in all cases,If he touched it with desire, then the view that it is obligatory (for him to do wudoo’) is very strong.
(AL-SHARH AL-MUMTI 1/234)