Does Touching the Private Part Invalidate Wudu?
Question

I know that ghusl suffices for wudu, whether or not the person who is junub does wudu before doing ghusl. But what about touching the penis and buttocks whilst doing ghusl? Does this require wudu after finishing ghusl?
Praise be to Allah.Does touching the penis invalidate wudu?
If the person who is junub does ghusl and touches his penis whilst doing ghusl, does that require wudu or not? 
That depends on a difference of scholarly opinion as to whether wudu is invalidated by touching the penis . Those who think that it does invalidate wudu say that it is obligatory for him to do wudu; those who think that it does not invalidate wudu do not think that it is obligatory for him to do wudu. 
It says in ash-Sharh al-Mumti‘: 
The scholars (may Allah have mercy on them) differed concerning touching the penis or vulva, and whether that invalidates wudu or not. There are several opinions: 

The first opinion, which is the view of the madhhab of Imam Ahmad, is that it does invalidate wudu. They quoted the following as evidence: 


The hadith of Basrah bint Safwan, according to which the Prophet (blessings and peace of Allah be upon him) said: “Whoever touches his penis , let him do wudu.”
The hadith of Abu Hurayrah (may Allah be pleased with him): “If one of you puts his hand on his penis with no barrier in between, then he must do wudu.” Another report mentions “the private part”.
A person may feel aroused when touching the penis or vulva, and something may come out without him realizing; in cases where it is thought likely that wudu may be rendered invalid, the ruling is connected to that (i.e., he must do wudu), as in the case of sleep. 


The second opinion is that touching the penis does not invalidate wudu. They quoted the following as evidence: 


The hadith of Talq ibn ‘Ali, according to which he asked the Prophet (blessings and peace of Allah be upon him) about a man touching his penis whilst praying: does he have to do wudu? The Prophet (blessings and peace of Allah be upon him) said: “No; it is just a part of you.”
The basic principle is that purity remains in effect and is not rendered invalid, and we do not move from this basic principle unless there is certain evidence to the contrary. The hadiths of Basrah and Abu Hurayrah [quoted above] are both da‘if (weak). Even if there was a possibility of them being sound, the basic principle is still that purity remains valid. The Prophet (blessings and peace of Allah be upon him) said: “He (one who thinks that he may have passed wind) should not exit the prayer unless he hears a sound or notices a smell.” If this applies to a tangible reason, it also applies to a textual reason; we cannot pay any attention to it unless it is known for certain. 


The third opinion is that if he touches it with desire, that invalidates his wudu, otherwise it does not. In this way it is possible to reconcile between the hadith of Basrah and the hadith of Talq ibn ‘Ali, and if it is possible to reconcile between two texts, then we must follow that before looking to see which text is stronger and which may abrogate the other, because reconciling between texts means acting upon texts, whereas looking to see which is stronger means rejecting the other. 

This is supported by the words of the Prophet (blessings and peace of Allah be upon him): “it is just a part of you.” That is because if you touch your penis without it provoking desire, it is like touching any other parts of your body; in that case it does not invalidate wudu. But if you touch it with desire then it does invalidate wudu, because the reason for the ruling is applicable in this case, which is the possibility of something being emitted that invalidates wudu without you realising it. So if a person touches it with desire, it becomes necessary to do wudu, but if that is without desire, then no wudu is required; that is because touching it in this way (with desire) is unlike touching any other part of the body. 
Some of the scholars reconcile between the two by noting that the instruction to do wudu in the hadith of Basrah is in the sense of it being mustahabb, and the instruction not to do it in the hadith of Talq is in the sense of it not being obligatory, based on the fact that he asked whether it was required, and he said “does he have to…?”, and the apparent meaning of the phrase translated here as “does he have to…” indicates that it is obligatory. 

The fourth opinion, which was favoured by Shaykh al-Islam Ibn Taymiyah, is that doing wudu after touching the penis is mustahabb (and not obligatory) in all cases, even in the case of desire. 

If we say that it is mustahabb, what that means is that it is prescribed and there is reward for doing it, and it is better to do it, so as to be on the safe side. As for the claim that the hadith of Talq ibn ‘Ali is abrogated, because he came to the Prophet (blessings and peace of Allah be upon him) when he was building his mosque at the beginning of the Hijrah, and he did not come back to him after that, this is not correct, for the following reasons: 

We do not move on to abrogation unless it is not possible to reconcile between reports, but reconciling between them is possible in this case.
In the hadith of Talq, there is a reason that cannot cease to be applicable, and if the ruling is connected to the reason that cannot cease to be applicable, then the ruling cannot cease to be applicable, because the ruling is connected to the reason for it. The reason in this case is the words “it is just a part of you.” It is not possible that a man’s penis could ever be said not to be a part of him, so it is not possible for this to be abrogated.
The scholars said that the timing of the hadith cannot be connected to the time when the narrator became Muslim or from the time he narrated it, because it may be that the narrator of the hadith heard it from another Sahabi. 

What is meant is that if two Companions narrate two hadiths that appear to contradict one another, and one of them came to Islam later than the other, we cannot assume that the hadith of the one who came to Islam later abrogates the hadith of the one who came to Islam before him, because it is possible that he is narrating from another Sahabi, or that the Prophet (blessings and peace of Allah be upon him) spoke of it after that. 
To sum up, if a person touches his penis, it is mustahabb for him to do wudu in all cases, whether that was with desire or not. If he touched it with desire, then the view that it is obligatory is very strong, but I cannot be definitive about it. However to be on the safe side he should do wudu.” 
In Sharh Bulugh al-Maram (1/259), the shaykh (may Allah have mercy on him) stated definitively that touching the penis with desire does invalidate wudu, but touching it without desire does not. 
According to this opinion, whoever touches his penis with desire whilst doing ghusl for janabah has to do wudu after he has finished doing ghusl, but if he touched it without desire, he does not have to do wudu. 
Does touching the buttocks invalidate wudu?
Touching the buttocks does not invalidate wudu; the difference of scholarly opinion only has to do with touching the anus, because one version of the hadith of Basrah bint Safwan says: “Whoever touches his private parts, let him do wudu.” Narrated by an-Nasai (444) and Ibn Majah (481); classed as sahih by al-Albani in Sahih an-Nasai. 
The difference of opinion on touching the anus is like the difference of opinion on touching the penis. 
With regard to the surrounding area, touching it does not invalidate wudu, such as touching the testicles or buttocks. 
Imam ash-Shafi`i (may Allah have mercy on him) said in al-Umm (1/34): “If he touches his testicles or buttocks or knees, but he does not touch his penis, then he does not have to do wudu.”
An-Nawawi (may Allah have mercy on him) said in al-Majmu‘ (2/42): Our companions said: What is meant by the backside is the point of exit (the anus); as for anything other than that, between the buttocks, it does not invalidate wudu and there is no difference of scholarly opinion on that point. End quote. 
Ibn Qudamah (may Allah have mercy on him) said: “Wudu is not invalidated by touching anything on the entire body other than the private parts, such as the area surrounding the private part or anus, and the testicles, according to the majority of scholars, because there is no text to suggest that and they do not come under the same heading as that which is mentioned in the text, so the ruling cannot apply to them.” “Al-Mughni, 1/119)
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And Allah knows best.