It is a nonsensical and a malicious claim which is gaining some popularity amongst the aberrations on the internet
The simplest way to disprove this allegation is to go to Islamic Jurisprudence.
As the charge is that of necrophilia (sex with a dead body) we can look into Islamic theology. If the allegation is true then the act of necrophilia would be allowed in Islam. So what does the expert (Ibn Hajar Haytami) say?
Well, he includes necrophilia in his list of sins . Thus we can realise necrophilia is not allowed in Islam and the Prophet did not engage in such a deed.
In fact if we consult Fiqh we realise “it is unlawful to look at the nakedness of the deceased or touch it” .Thus further showing sex with the deceased (dead) cannot possibly be allowed. This further shows the Prophet did not engage in such a deed as if he did then the practice of necrophilia would have been allowed in Islam.
Now we know the claim of necrophilia against Prophet Muhammad is incorrect we can analyse the methodology used by the claimant (Zakaria Botros) and the narration he uses. This course of action will suffice for us to be fully conversant with this claim and able to explain why the claims are erroneous (false).
It is important to be able to explain it as there is a growing number of willing propagators of such falsehood, thus this false claim will only become popular if good people sit on their hands.
Analysing the Allegation: Authentic?
The narration which is used is from a book named Kanza ul Amal. This book contains fabricated and weak narrations, thus is not recognised as an authoritative source (individual narrations need to be checked).
Regardless of the authenticity let’s still look at the narration and context to gain understanding so we can realise the actual meaning of such a narration (regardless of authenticity)
Narrated by Ibn Abbas:
"I (Muhammad) put on her my shirt that she may wear the clothes of heaven, and I SLEPT with her in her coffin (grave) that I may lessen the pressure of the grave. She was the best of Allah's creatures to me after Abu Talib"... The prophet was referring to Fatima, the mother of Ali.
Looking at the narration alone one would not cry “necrophilia” or any wrong doing as “sex” is not mentioned. However, simply looking at the narration’s English translation one would find it odd. Sleeping with somebody in a coffin (grave) is an odd occurrence indeed. However, once the context is given we realise what actually happened.
The Context and Explanation
Firstly the translation of “I slept” does not best convey the meaning based on the context, the Arabic word translated as “I Slept” is Idtaja’ (اضطجع ). This word can either mean:
lie down, lie, recline, repose .
I hope you have noticed within the list of definitions (lie down, lie, recline, repose) the word “sleep” (or “sex”) does not appear. Lane’s Lexicon does indicate it can refer to sleeping too:
lay upon his side; or] he laid his side upon the
ground; [and simply he lay; and he slept 
Though the word can refer to sleep, I have seen NO indication in Lane’s Lexicon nor the other dictionary which indicates the word means sex. (I will elaborate on this later on in this paper whilst discussing Father Zakaria’s bizarre and fallacious interpretation of the narration)
So we are left with the question: did Muhammad sleep or lie in the grave?
The context explains it all, as it was a grave we realise the word cannot possibly mean “sleep” but rather it means “lie/lay in the grave”.
This actually makes sense with the other bits of context we have at our disposal; “When the grave was prepared Muhammad himself examined it and placed her into the grave” .
Thus, it is reasonable to think the examination procedure also involved Muhammad lying in the grave. This would not have been at length in terms of duration (time). Therefore we realize Muhammad simply laid in the grave to make sure it was comfortable for his deceased foster mother as well as to honour the lady as it would be seen as a fabulous honor to be resting in a place where a Prophet of God had previously laid.
Did Muhammad Lie with his Foster Mother (Fatima Bint Asad) in the Grave?
It does not appear so as the process of investigating/examining the grave would have been PRIOR (before) lowering Fatima Bint Asad into the grave. Therefore Muhammad would have reclined (lied) in the grave in order to check the grave before Fatima was placed in the grave, thus he would not have lied with her. Furthermore, there were two types of graves in vogue at the time of the Prophet which were Lahd and Shaqq (shiq) , .
The Shaqq type of grave is characterized by a niche within the grave for the dead body to be placed within. So it is impossible to lie with the body due to the niche. 
The Lahd form of grave is characterized by a lateral hollow which is dug into the side of the base of the grave for the body to be placed . This type of grave makes lying with the deceased body risky as the earth could cave in on top of the body and the one who is lying with the deceased.
Thus, it seems the laying in the grave for examination purposes was done prior to Fatima being lowered into her resting place. This is despite the Arabic phraseology used literally denoting “with”:
اضطجعت معها في قبرها
However, even if one takes it literally it does not mean wrong doing took place and it certainly does not refer to sex.
If Muhammad did lie with his foster mother whilst she was in the grave in order to check for comfort and honor her before the companions filled the grave it would only have been for a short time and this would have been witnessed by other people too. There is nothing wrong with lying in the grave to ensure comfort for your foster mother and honor; in fact it was an act of great compassion.
Having established all the above we can move on to discuss and deconstruct the misdirection of Father Zakaria (the one who initially made this fallacious claim)
This seems to be a transcript of Father Zakaria’s explanation to the narration:
The Arabic scholar Demetrius explains: "The Arabic word used here for "slept" is "Id'tajat," and literally means "lay down" with her. It is often used to mean, "lay down to have sex." Muhammad is understood as saying that because he slept with her she has become like a wife to him so she will be considered like a "mother of the believers." This will supposedly prevent her from being tormented in the grave, since Muslims believed that as people wait for the Judgment Day they will be tormented in the grave. "Reduce the pressure" here means that the torment won't be as much because she is now a "mother of the believers" after Muhammad slept with her and "consummated" the union."
Firstly, who is “Demetrius”? Zakaria gives no introduction to this scholar. Why? I have had a look at Lane’s Lexicon and I did not get the inference the word meant sex. However, this is a smaller point in the deconstruction of Zakaria’s claim.
We will look at Father Zakaria’s unauthorised interpretation of the event and show the holes within his reasoning.
Have Sex with Her in Order to give her a Special Status?
“Muhammad is understood as saying that because he slept with her she has become like a wife to him so she will be considered like a "mother of the believers””
Zakaria’s premise is that Muhammad had sex with Fatima because he wanted her to attain special status as the “mother of the believers”. Well, Zakaria’s premise falls flat on its face because Fatima bint Asad already had the special status of being Muhammad’s foster mother. 
In the transcript this information has been withheld (i.e. nobody is told of her special status as the foster mother of Muhammad). Why is this information not relayed to us in the transcript which is circulating the internet? It is because Zakaria’s premise is thrown into doubt immediately if we are told she already has a special status. Thus if she already had a special status then there would be no need for her to be given the special status of being “like a wife to him” as she was already like a mother to him (Muhammad).
So Father Zakaria’s reasoning is flawed from the start. However, it gets worse for the Zakaria.
“She has become like a wife to him”
Father Zakaria is trying to fool us. He is claiming Muhammad had sex with Fatima in order for her to have a status of a wife of Muhammad and thus the title of “mother of the believers”.
Zakaria is either ignorant or dishonest.
Muhammad could NOT possibly have taken Fatima Bint Asad as a wife as Islamic Law dictates consent be given by BOTH parties in a marriage; of course marrying a dead person would not be allowed simply based on this injunction. Father Zakaria knows this but continues with his fanciful claim because it suits his agenda to besmirch the reputation of the Prophet Muhammad
So the point here is that Fatima could never have become his wife through such an act, despite Father Zakaria’s nonsensical pleadings. Thus Father Zakaria is looking even more foolish in his claim. It gets more embarrassing for Father Zakaria
“Muhammad did this to save her from the torment of the grave”?
Father Zakaria is showing signs of a fertile imagination and utter ignorance.
If we consult Ahadith literature we will realise Muhammad’s PRAYER made the grave a better abode for people (Hadith) through the grace of God. This shows us if Muhammad seriously felt Fatima Bint Asad was in danger of the punishment of the grave he would have simply PRAYED for her grave to be a better dwelling. 
Thus we realise Zakaria’s debauched idea that sex (or marriage) is required to save a person from the punishment of the grave is warped and fallacious to say the least. It gets worse for Father Zakaria.
“Muslims believed that as people wait for the Judgment Day they will be tormented in the grave”
Zakaria is showing signs of clear ignorance. Muslims of course believe in the punishment of the grave but those whom Allah is pleased with are NOT punished. Fatima Bint Asad is considered a saintly woman thus Muslims do not believe she is subjected to the punishment of the grave.
In fact the Muslim belief concerning pious people (such as Fatima Bint Asad) is that their graves will reflect Paradise and will be very comfortable and blissful indeed.
'The grave is a garden of paradise or a pit of hell." (Mishkat)
Rasulullah said, 'The grave is a garden of paradise or a pit of hell.' (Mishkat).
Concerning the pious people (such as Fatima Bint Asad) “A believer will answer all three questions and he will be honored with the clothing of Jannah. The window of Jannah will be opened for him and he will enjoy the sight of Jannah” (Mishkat) (appendix 1)
Thus we realise the grave of a saintly woman (i.e. Fatima Bint Asad) would not be one of torment but of splendour, peace and bliss. She will also see Jannah (Paradise).
This just illustrates Father Zakaria’s ignorance and shows his crackpot idea of Muhammad having sex with his foster mother in order to save her from torment is unadulterated nonsense and a product of a very strange mind indeed.
Father Zakaria’s Hypocrisy
The one making this odd claim is a Christian and it just goes to reveal his hypocritical nature because the same word (a construct of Idtaja) is used in the Arabic Bible and it is not translated as sex but is translated as “LAID”. Does Father Zakaria want to be consistent now and withdraw his silly claims?
Please also bear in mind the dictionary references (given earlier) which disprove Father Zakaria’s malicious claims, well the Bible is now disproving hm.
The same Arabic word is used in the Bible (2Kings 4:32) and it is translated as “laid” and not sex or anything of that nature:
وَدَخَلَ أَلِيشَعُ الْبَيْتَ وَإِذَا بِالصَّبِيِّ مَيْتٌ وَمُضْطَجعٌ عَلَى سَرِيرِهِ.
English Translation: And when Elisha was come into the house, behold, the child was dead, and laid upon his bed. (KJV)
This along with the dictionary references shown earlier just further indicates the narration in question has nothing to do with sex.
Clarification: Why Do You Say There Was No Sex?
I think this point needs reiteration and summarizing so nobody is in any doubt. It is a silly, unfair and false claim to say sex was involved, consider the following:
*The word used (Idtaja’) does not infer sex. It simply refers to lying down or sleeping. The meaning of lying down is further highlighted by the context. There is NO way it refers to sex. NO authority would consider it meaning sex. In fact if the narrator wanted to convey the idea of sex/marriage taking place he would have used a totally DIFFERENT Arabic word (i.e. a construct of nikah).
*The same Arabic word is used in the Bible (2Kings 4:32) and it is translated as “laid” and NOT “sex” or “sleep”.
*Islam does not allow sex with dead people (already mentioned above). Islam is based on the deeds and actions of the Prophet as well as the Quran. Thus if Muhammad did involve himself in this type of activity it would be allowed within Islam. This just goes to show Muhammad never committed such an act.
*Fiqh (Jurisprudence) tells us it is not allowed to touch the nakedness of the deceased, as most Fiqh is also based upon Muhammad’s actions we can realize Muhammad did not touch any deceased body in a sexual manner.
*Fatima Bint Asad was deceased, thus meaning a marriage between Muhammad and her or any subsequent conjugal (sexual) relations would be rejected by Islam
*The burying of a deceased person is a community effort thus Muhammad would not have been alone whilst at the grave side. Thus it would be absurd to suggest somebody had sex with a deceased woman whilst everybody sat and watched
* Muhammad’s enemies would have mentioned it and used it against him if he did commit such an act. Muhammad’s enemies never accused him of necrophilia. This further shows this allegation of necrophilia is false and baseless.
*As we have already mentioned, the dictionary references do not indicate sex but lying down/sleeping (the context of which simply refers to lying down). These references are further strengthened by the context.
*Also, the two grave types (Lahd/Shaqq) would physically render the grave as unsuitable for sex.
*The body of the deceased is meant to be handled with care  so much so that a bone of the body must not be broken. Of course it goes without saying this would mean sex would be out of the question.
*Fatima bint Asad was the foster mother of Muhammad. “When Muhammad heard Fatima Bint Asad had died, he immediately went to her house sat beside her body and prayed for her soul”
*“When the grave was prepared Muhammad himself examined it and placed her into the grave. Thus, she was one of the few people whose graves were examined by Muhammad”. Examination of a grave does involve lying down in a grave but does NOT involve sex.
* It is dehumanizing and a disconnection from reality to believe a world religion of nearly 2 billion will be founded by a man who involved himself in necrophilia
Muhammad was doing what any loving and caring person should do; that was focussing on the well being of his relative (foster mother and aunt, Fatima bint Asad) ) both in this life and the hereafter. There was no sex or wrong doing involved.
This heart warming story of compassion and love for one’s family member is now being hijacked by the debauched and hateful mind of a few who are motivated by hatred and destruction.
Father Zakaria should be ashamed with himself; this man has a poor reputation in the Arab world, both Christians and Muslims will see him as a man looking for controversy and attention whilst viewing him as a crackpot figure.
I have had some dealings with the English speaking version of Father Zakaria and he, too, is seen as a man motivated by deviance and outright deception. This man’s deception extends to making up his own BIBLICAL verses up! (Appendix 2)
Fair people (both Muslims and Christians) should be wary of such characters and help fight their misinformation. If you happen to be somebody who dislikes Islam or a supporter of such perpetuators of outrage and dishonesty then I urge you to have a rethink and refrain from supporting such individuals financially as they will ultimately be laughing all the way to the bank at the expense of the truth.
There is no copyright restriction on this work so feel free to share it in order to further the truth
May Allah’s peace and blessings be upon Prophet Muhammad and may Allah send more good upon Fatima bint Asad. Ameen
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1. Reliance of the Traveller, Ahmad ibn Naqib al Misri, edited and translated by Nuh Ha Mim Keller, Amana Publications, 1994 [W52.1, 343]
2. Reliance of the Traveller, Ahmad ibn Naqib al Misri, edited and translated by Nuh Ha Mim Keller, Amana Publications, 1994 [g2.7]
3. Online Arabic-English dictionary, http://www.stars21.com/dictionary/English-Arabic_dictionary.html
4. An Arabic-English Lexicon by Edward William Lane, Williams and Norgate, 1872
6. Bulug al Maram, compiled by Al-Hafiz ibn Hajar al-Asqalani (with brief notes from Subul us Salam), Darussalam Publishers and Distributors, 2002 pg 186
7. Reliance of the Traveller, Ahmad ibn Naqib al Misri, edited and translated by Nuh Ha Mim Keller, Amana Publications, 1994 g5.3
8. Ibid. g5.3
9. Bulug al Maram, compiled by Al-Hafiz ibn Hajar al-Asqalani (with brief notes from Subul us Salam), Darussalam Publishers and Distributors, 2002 pg179 Hadith no 447 (see appendix 3)
10. Reliance of the Traveller, Ahmad ibn Naqib al Misri, edited and translated by Nuh Ha Mim Keller, Aman Publications, 1994 w52.1/119
Rasulullah said, 'When a person is buried and the people go away, two angels approach the deceased and ask three questions, a) Who is your lord? b) What is your religion? and c) Who is he (Rasulullah )?. A believer will answer all three questions and he will be honored with the clothing of Jannah. The window of Jannah will be opened for him and he will enjoy the sight of Jannah. On the contrary, a disbeliever will express regret at not being able to answer the questions. Upon that, an angel who is blind and deaf is appointed to punish him. Blind so that the angel does not see the punishment and feel mercy and deaf so that the punishment is not heard. The hammer used to punish a disbeliever is so heavy that it can reduce a mountain to dust. The disbeliever screams with pain and every creation can hear him besides human and Jinns.' (Mishkat)
Rasulullah said, 'The grave is a garden of paradise or a pit of hell.' (Ibid)
The English speaking version of Father Zakaria makes up his own Biblical verse in order to fit in with a strange “mathematical code” idea:
Such is the disrespect for the truth people of this nature possess.
Narrated Abu Huraira ®: Regarding the story of a woman who used to sweep the mosque. The Prophet (S) asked about her and they ( the Companions) told him she had died. He (S) then said, “why did you not inform me?” and it appeared as if they had considered her as of little importance. He (S) said, “show me her grave”, and when they did so he prayed on her. And Muslim added : He (S) then said, “these graves are full of darkness for their occupants, but Allah will illuminate them (the graves) for them (the occupants) because of my prayer on them”.
Another example of Muhammad caring for people in the grave
Narrated Ibn 'Abbas: The Prophet once passed by two graves and said, "These two persons are being tortured not for a major sin (to avoid). One of them never saved himself from being soiled with his urine, while the other used to go about with calumnies(to make enmity between friends)." The Prophet then took a green leaf of a date-palm tree, split it into (pieces) and fixed one on each grave. They said, "O Allah's Apostle! Why have you done so?" He replied, "I hope that their punishment might be lessened till these (the pieces of the leaf) become dry." (See the foot-note of Hadith 215). (217)
Narrated Ibn 'Abbas: Once the Prophet, while passing through one of the grave-yards of Medina or Mecca heard the voices of two persons who were being tortured in their graves. The Prophet said, "These two persons are being tortured not for a major sin (to avoid)." The Prophet then added, "Yes! (they are being tortured for a major sin). Indeed, one of them never saved himself from being soiled with his urine while the other used to go about with calumnies (to make enmiy between friends). The Prophet then asked for a green leaf of a date-palm tree, broke it into two pieces and put one on each grave. On being asked why he had done so, he replied, "I hope that their torture might be lessened, till these get dried." (215)
Read more: http://www.islamonline.net/servlet/Satellite?pagename=IslamOnline-English-Ask_Scholar/FatwaE/FatwaE&cid=1119503543856#ixzz0ujoshLtE
Claim in full:
(Narrated by Ibn Abbas:
"I (Muhammad) put on her my shirt that she may wear the clothes of heaven, and I SLEPT with her in her coffin (grave) that I may lessen the pressure of the grave. She was the best of Allah's creatures to me after Abu Talib"... The prophet was referring to Fatima , the mother of Ali.
The Arabic scholar Demetrius explains : "The Arabic word used here for "slept" is "Id'tajat," and literally means "lay down" with her. It is often used to mean, "lay down to have sex." Muhammad is understood as saying that because he slept with her she has become like a wife to him so she will be considered like a "mother of the believers." This will supposedly prevent her from being tormented in the grave, since Muslims believed that as people wait for the Judgment Day they will be tormented in the grave. "Reduce the pressure" here means that the torment won't be as much because she is now a "mother of the believers" after Muhammad slept with her and "consummated" the union."
now, i know the same word اضطجع
is used in 2 king:4:32-34
means lay dawn , it doesn't mean he have sex with the boy.
Lack of authenticity in Kanzal ul Amal
Fatima looked after Muhammad during his youth.
Anas bin Malik says that when Muhammad heard Asad had died, he immediately went to her house sat beside her body and prayed for her soul.
"My dear mother, may God keep you under His Protection. Many times you went hungry in order to feed me well. You fed me and clothed me on delicacies that you denied yourself. God will surely be happy with these actions of yours. And your intentions were surely meant to win the goodwill and pleasure of God and success in the Hereafter."
He gave his shirt to be used as part of her shroud. When the grave was prepared Muhammad himself examined it and placed her into the grave. Thus, she was one of the few people whose graves were examined by Muhammad. Fatimah is buried in Jannatul Baqee' cemetery in Madinah, Saudi Arabia.
Here is a video refuting this claim of Zakaria Butrous. It also contains some claims related to Zakaria Butrous' past and morality. I'm not sure of the authenticity of the claims related to Butrus but the refutation is useful
What is Takiya, Taqiyya?
Did Ali and Abu Bakr Really Burn People?
Stupid claim of Aisha not having reached puberty at time of consummation
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