I suffer from many uncertainties when doing wudu. What this means is that when I wash my arms, I wash the top of the arm, then I tell myself that it is not sufficient to rub the other side of my arm, because this is regarded as wiping over it and is not washing. This makes me turn my arm over under the tap so that the water will reach the other side of my arm. And I do the same for my feet. Also, when washing my face, I feel that the water is not reaching the front of my head or the temples when I fill my cupped hands with water, which makes me put my face under the tap so that the water will reach those places. I hope that you – may Allah reward you with good – can explain to me in detail what is the difference between washing and wiping, and is it sufficient to pour the water over part of the limb then rub the rest of the limb with that water?
Firstly:
You should understand – may Allah have mercy on you – that it is not obligatory to rub the skin when doing wudu or ghusl, according to the majority of scholars, and it is sufficient to make the water reach all of the body when doing ghusl; only Malik (may Allah have mercy on him) held a different opinion regarding that.
An-Nawawi (may Allah have mercy on him) said: Our view is that rubbing the limbs in ghusl and in wudu is Sunnah, and is not obligatory. So if he pours water on himself and it reaches the limb, without him touching it with his hands or dipping himself in a large amount of water, or standing under a downspout or in the rain with the intention of doing ghusl, and the water reaches his hair and skin, his wudu and ghusl are valid. This was stated by all the scholars except Malik and al-Muzani, who stipulated that rubbing the limbs is essential in order for ghusl and wudu to be valid.
Our companions quoted as evidence for that the words of the Prophet (blessings and peace of Allah be upon him) to Abu Dharr (may Allah be pleased with him): “When you find water, make it touch your skin.” And he did not instruct him to do more than that. It is an authentic hadith, and there are many similar hadiths.(Al-Majmu`, 2/214).
Ibn Qudamah (may Allah have mercy on him) said: He does not have to pass his hands over his body when doing ghusl and wudu, if he is certain or thinks it most likely that the water has reached all of his body. This is the view of al-Hasan, an-Nakha`i, ash-Sha`bi, Hammad, ath-Thawri, al-Awza`i, ash-Shafa`i, Is-haq and as-hab ar-ra’y.(Al-Mughni, 1/290).
Based on that, what is required when doing wudu is to wash each part once, making sure that the water reaches all of it, even if that is done by dipping the limb in water or putting it under the tap and the like. It is not stipulated that you should turn your arm over or put your face under the tap; rather all of that is a kind of unnecessary effort in complying with Islamic commands. You do not have to rub your limbs unless you cannot make the water reach some parts of them except by rubbing; in that case you must rub them, but you should also be careful not to let these intrusive thoughts (waswasah) control your actions.
The difference between washing and wiping is that in the case of washing, it is stipulated that the water should flow over the part that is being washed, in contrast to wiping, in which that is not stipulated; rather what is stipulated is that you should pass your wet hands over the part in question, without pouring water over it or making water flow over it, as when wiping over the hair and so on.
Secondly:
You should understand that what is certain cannot be undermined by what is uncertain. So if you are certain of something, then once you have become certain of it, you should pay no attention to uncertainty or doubt that arises after that. Once you have done something, do not pay any attention to any uncertainty or doubt that arises after doing it. So if you wash your arm well and you are certain that the water reached all of the limb, do not pay any attention after that – not even for a moment – to any uncertainty that tells you that you did not rub your arm properly, because this is an intrusive thought or whisper that comes from the Shaytan. So do not go along with the intrusive thought that he instils in your mind, because allowing intrusive thoughts to control your mind and following what they tell you to do will cause you a great deal of trouble, hardship, distress and anxiety, and that could lead to insanity.
What you have said about the way in which you do ghusl, and your unnecessary efforts in that regard, is going against what is required according to Islamic teachings, and it is a kind of intrusive thoughts (waswasah) that make you go to unnecessary lengths. So strive to divert your thoughts from that and do wudu as other people do it.
For more information on intrusive thoughts and the remedy for them, please see the answer to question no. 100268.
And Allah knows best.