Firstly: 

Before answering your questions, we should pause to note a few things. We are very happy that you have written to us. You have told us about what you are suffering from of the shaytaan gaining power over you, and we are saddened to learn that your situation is so bad, but we hope that our Lord will help you and guide you to the best of attitudes and deeds. We think that the fact that you have memorized Qur’aan, and that you love obedience and worship, especially prayer, will be a means to your being protected and guided, in sha Allaah. 

Secondly:

 You should realize that what you are doing – the secret habit – is something that has been done by many, but Allaah has enabled them to repent from it. The reasons why they stopped it are many. Some of them gave it up out of fear of Allaah, and out of shyness before Him and His noble angels, because they believed that Allaah can see them, so they gave it up out of shyness before Him. They knew that the angels can see them, so they gave it up out of shyness before them, and they knew that Allaah has forbidden it, and they feared His punishment. Some of them gave it up when they thought about its many harmful effects on the soul and the body; they knew that it would affect their marital lives, so they gave it up lest its consequences affect them. Some of them gave it up because it was contrary to sound human nature and reason that Allaah has bestowed on them.

 We think that you will give it up for all the reasons mentioned above. Allaah has given you strength and youth, and health and well being, and righteousness and guidance. These are blessings for which you cannot give enough thanks even if you live as long as Nooh (peace be upon him), praying and obeying your Lord. Is this the way to show gratitude for these blessings? The fact that you have memorized the Book of Allaah and you know the ruling on the one who does not pray should motivate you to think carefully about how this habit has led you to neglect the greatest of the practical pillars of Islam, namely prayer. By giving it up you will be joining the mushrikeen and apostates who have left the religion of Allaah! We think positively of you and we think that you will give up this habit out of shyness before Allaah and His angels, and out of fear of His punishment, and because of the bad effects it has on the soul and body, and because Islam says that it is haraam. 

This is what we think of you, and we hope that you will not let us down. We hope, after all this, that you will think about just two things: 

1 – What if one of the great Shaykhs or scholars whom you trust and respect were to see you? What if they saw you when you were engaging in this bad habit? Would you ever enjoy life after that and would you be able to face them after that? 

Remember that Allaah can see you and is watching you, and that His noble angels can see you. 

2 – We hope that you will think about the possibility that you may die whilst engaging in this habit! Would you like your life to end in that way? Would you like to be raised from your grave in that state? Would you like to die in a state of janaabah due to a haraam action? 

We hope that you will think about these two things, and will write and tell us that you have pledged not to do that and that you are taking measures to strengthen your heart with faith and certain belief, keeping away from all things that may lead to doing this habit, such as looking at haraam things, being alone with a member of the opposite sex, reading provocative stories, and other things. We are waiting for a letter from you telling us that you have repented to Allaah and that you are maintaining your tahaarah (purity) and praying regularly. We hope that you will not let us down and that we will hear from you soon.  

Thirdly: 

Remember that emission of maniy with desire means that ghusl is obligatory, and it is not permissible for you to do wudoo’ only for prayer after you have become junub. There is no difference of scholarly opinion concerning this. We would never tell you to do wudoo’ and pray because it is better than not praying at all, because this would be a deceitful fatwa and it would be deceiving you. Rather we say to you with certainty that prayer offered without doing ghusl in the event of janaabah is invalid, and doing that knowingly is a kind of mocking sharee’ah.  

Praying without having purified oneself is a major sin for which a person deserves to be punished in the grave. Listen to this hadeeth which was narrated by al-Tahhaawi in Mushkil al-Athaar from ‘Abd-Allaah ibn Mas’ood (may Allaah be pleased with him) from the Prophet (peace and blessings of Allaah be upon him) who said: “It was commanded that one of the slaves of Allaah be given one hundred lashes in his grave, but he kept asking Allaah and calling upon Him until it was made one. And his grave was filled with fire. When it ceased, he woke up and said: Why did you flog me? They said: You offered a prayer without having purified yourself, and you passed by one who was being wronged and you did not help him.” 

Classed as hasan by al-Albaani in Saheeh al-Targheeb (2234). 

This is the punishment for a person who offered a single prayer without having purified himself. Are you able to bear that? 

Beware of responding to the tricks of the shaytaan who is calling you to give up prayer. Your own nafs may make that appear attractive to you too, seeking to escape from this punishment. 

But this is not the way to flee from this punishment. The likeness of that is the likeness of one who flees from one thing to something that is even worse than it. 

Giving up prayer is kufr that puts one beyond the pale of Islam, and the kaafir will abide in Hell forever and ever. Understand this and be certain of it; perhaps it will make you understand the state to which this bad habit has brought you, and perhaps you will hasten to set things straight and sort out the mess that your life has become because of this action. 

Shaykh al-Islam Ibn Taymiyah (may Allaah have mercy on him) said: 

Purification from janaabah is obligatory, and no one has the right to pray in a state of either janaabah or minor impurity until he has purified himself. If a person prays without having purified himself in the manner prescribed in sharee’ah, thinking that it is permissible to do that, he is a kaafir. If he does not regard that as permissible, then there is a difference of scholarly opinion as to whether he is a kaafir, but he deserves a severe punishment. 

Majmoo’ al-Fataawa (21/295). 

Fleeing from punishment is achieved by fleeing to Allaah, may He be exalted: “So flee to Allaah (from His Torment to His Mercy __ Islamic Monotheism). Verily, I (Muhammad صلى الله عليه وسلم) am a plain warner to you from Him” [al-Dhaariyaat 51:50]. 

You flee from everything that you fear, except Allaah. So if you fear Him, flee to Him. Fleeing to Him means fleeing from that which Allaah hates to that which He loves, fleeing from disobedience to obedience, from kufr to faith, from innovation to Sunnah, from heedlessness to remembrance. 

We ask Allaah to purify your heart and keep you chaste, and to help you to do that which He loves and which pleases Him. 

And Allaah is the Source of strength.