He is paralyzed and suffers from involuntary urination; how can he purify himself and pray, and can he do tayammum in the event of janaabah?
Question

                I am paralyzed, praise be to Allah, and I suffer from involuntary urination, hence I urinate a great deal, and I cannot always change my clothes. I want to know what my situation is with regard to prayer. Should I do wudoo’ or tayammum, noting that I am able to do wudoo’? I also want to know how I can deal with maniy (semen) if it is emitted, knowing that I can only do ghusl once or twice a week.
Praise be to Allah.Firstly:
We ask Allah, may He be exalted, to heal you and grant you well-being, and to reward you for what has befallen you.
If a person suffers from involuntary urination, he must use something to prevent the urine spreading, such as a dressing or diaper, then he must do wudoo’ for every prayer. If it is too difficult for him to do wudoo’ for every prayer, then it is permissible for him to put Zuhr and ‘Asr together, and put Maghrib and ‘Isha’ together, at the time of the earlier or later prayer.
He does not have to change the diaper if he has put it on properly so that it does not leak.
It says in Sharh Muntaha al-Iraadaat (1/120): In the case of anyone who experiences prolonged impurity, such as a woman who suffers istihaadah (non-menstrual bleeding), or one who is affected by urinary incontinence, or continuous emission of madhiy (prostatic fluid) or wind, they should wash the site that is contaminated by impurity, in order to remove it, and wrap it, i.e., take measures to prevent the impurity coming out [and spreading], as much as possible, such as using a pad of cotton and tying it with a clean cloth.…
They do not have to wash the area and wrap it for every prayer, so long as there is no negligence, because when such things happen all the time, it is not possible to avoid them.
The one who is constantly emitting that which invalidates wudoo’ should do wudoo’ when the time for each prayer comes, if something is emitted [between the prayers]. End quote.
Some of the scholars are of the view that using a dressing or diaper is not obligatory. This is the view of the Maalikis. You can follow this view, if it is too difficult for you to use a diaper.
Al-Hattaab al-Maaliki (may Allah have mercy on him) said: It is recommended in al-Mudawwanah to wrap it with a cloth. Sanad said: It is not obligatory, because praying wearing that cloth, which is contaminated with impurity, is the same as praying in his (contaminated) garment (which is contaminated).
Sanad said: Is it mustahabb to change the cloth? Al-Ibyaani said: It is mustahabb for him to do that when he wants to pray, and then wash it. According to the view of Sahnoon, it is not mustahabb, and washing the private part is easier for him than that.
End quote from Mawaahib al-Jaleel (1/143).
With regard to prayer in particular, if it is too difficult for you to purify yourself (wudoo’) and offer each prayer at its time, then you may put two prayers together. So you can pray Zuhr and ‘Asr with one wudoo’, and do likewise with Maghrib and ‘Isha’.
Shaykh al-Islam Ibn Taymiyah (may Allah have mercy on him) said in Majmoo‘ al-Fataawa (24/14): The one who is sick and the woman who is suffering from istihaadah may put prayers together. End quote.
From the above, it is clear that the matter may be addressed in the following order:

You can protect yourself with a piece of cotton or a dressing, and you do not have to change it or wash the place for every prayer, so long as you have put it on and tied it properly, but you must do wudoo’ after the time for each prayer begins.
If it is too difficult for you to tie it properly, then you may follow the Maaliki view which says that that is not obligatory.
You have a concession allowing you to put prayers together.

Secondly:
What is required of the one who is able to use water is to do wudoo’, and tayammum is not valid in his case; rather he should hire someone to help him do wudoo’, if he is unable to do it by himself and he can afford to pay someone to help him.
It says in Kashshaaf al-Qinaa‘ (1/102): If the amputee and the like, such as one who is paralyzed or sick, is unable to do wudoo’ himself, but he can find someone to help him to do wudoo’ or ghusl in return for a reasonable fee that he can afford, without that affecting him or those on whom he is obliged to spend, then he must do that, because in that case he is like one who is healthy.
If he can find someone who can help him to do tayammum, but he cannot find someone to help him to do wudoo’, then he must do that, like a healthy person who is able to do tayammum but not wudoo’.
If he cannot find anyone to help him to do wudoo’ or tayammum, because he cannot afford to pay them, or he is not able to find someone whom he could hire, then he must pray as he is. It says in al-Mughni: I do not know of any scholarly difference of opinion concerning that.
The same applies if he cannot find anyone to help him except at a higher price than is usual, unless the price is only slightly higher.
The same ruling applies to istinja’ (cleaning oneself after relieving oneself).
If someone offers to help him purify himself voluntarily, he becomes obligatory for him to clean himself.
End quote.
So long as you are able to do wudoo’, doing it is obligatory in your case, and tayammum is not valid.
Thirdly:
If ghusl becomes obligatory because of a wet dream, for example, and you are not able to do ghusl yourself, and there is no one who will help you to do ghusl, either for free or for a fee that you can afford, in that case it is permissible to do tayammum to remove the janaabah, as is known from the report quoted above.
It is not permissible to be heedless concerning this matter; rather you should strive to do ghusl yourself or to hire someone to help you to do ghusl if you cannot find someone who will volunteer to do it. If you are unable to do that, then you may move to the option of tayammum, until you become able to do ghusl, in which case you should then do it.
Having someone else to help you to do ghusl means that they should pour water over you, whilst your ‘awrah – which is the area from the navel to the knee – remains covered.
Please see the answers to questions no. 101816 and 40204.
Some of the scholars are of the view that if someone is unable to do ghusl but is able to do wudoo’, he should do tayammum to remove janaabah, then do wudoo’. Undoubtedly this is more prudent and is better, and avoids a considerable difference of scholarly opinion concerning the matter.
If you are able to do wudoo’, but are not able to do ghusl, as you mentioned in your question, then you should do tayammum to remove the janaabah, then do wudoo’ for prayer.
Shaykh al-Islam Ibn Taymiyah (may Allah have mercy on him) said:
If a man or woman is able to do wudoo’ and tayammum, they should do that.
If they limit it to tayammum, that is acceptable, according to one of the two views narrated from the scholars.
The view of Abu Haneefah and Maalik is that purification using water and purification by doing tayammum should not be combined; in other words, the original method and the alternative should not be combined. Rather it should be either one or the other.
The view of ash-Shaafa‘i and Ahmad is that the individual should wash whatever he can with water, and do tayammum for the rest.
If he does wudoo’ and tayammum, it does not matter which of them comes first, but doing wudoo’ first is better.
End quote from Majmoo‘ al-Fataawa (21/453).
Shaykh ‘Abd al-‘Azeez ibn Baaz (may Allah have mercy on him) was asked:
I had surgery on my back, and I am able to do wudoo’ for prayer with difficulty. One night I had a wet dream, and I was not able to have a bath, lest it affect the wounds from my surgery. Is it sufficient for me to do tayammum, and is it essential for me to do wudoo’ after tayammum, or what should I do in this situation? I hope that you can advise me about that.
He replied:
What is required of the Muslim is to fear Allah as much as he is able to in all his affairs, because Allah, may He be glorified, says (interpretation of the meaning): “So fear Allah as much as you are able” [at-Taghaabun 64:16].
And the Prophet (blessings and peace of Allah be upon him) said: “Whatever I forbid you to do, avoid it, and whatever I enjoin you to do, do as much of it as you are able.” Agreed upon.
If a sick person is not able to do wudoo’ or ghusl, then tayammum is sufficient in his case, because Allah, may He be glorified, says (interpretation of the meaning):
“…But if you are ill or on a journey or one of you comes from the place of relieving himself or you have contacted women and do not find water, then seek clean earth and wipe over your faces and hands with it. Allah does not intend to make difficulty for you, but He intends to purify you and complete His favor upon you that you may be grateful”
[al-Maa’idah 5:6].
If someone is unable to use water for wudoo’ or ghusl, he comes under the same ruling as one who is unable to find water.
If you are able to do wudoo’, but not ghusl, then you should do wudoo’, and do tayammum in the place of ghusl, as we have quoted above the verse in which Allah, may He be glorified, says (interpretation of the meaning: “So fear Allah as much as you are able” [at-Taghaabun 64:16]. And Allah is the source of strength. End quote.
And Allah knows best.