All praise belongs to Allāh and may peace and blessings be upon the prophet Muhammad.
The title may surprise many since almost all people know who their fathers are. The title does not exist merely as a catchy one but alludes to a very important principle of the sharī’ah that relates to many practical and complicated matters of life. Understanding this principle clarifies the wisdom behind many rulings and gives us better insight into the philosophy of the sharī’ah. Both the principle and the actual issue will be explained in this article.
Allāh says in the Qur’an,
“Those who pronounce the dhihār among you [to separate] from their wives – they are not [consequently] their mothers. Their mothers are none but those who gave birth to them. And indeed, they are saying an objectionable statement and a falsehood. But indeed, Allāh is Pardoning and Forgiving.” 
The mother of a person can be defined as either the one who produces the egg, the one that contributes to the child’s DNA, or the one that gives birth to the child. Although in the overwhelming majority of children all three of the above are the same woman, it does rarely occur that a married lady may give her egg, either by donation or by sale, to another woman (a surrogate mother) to be fertilised by a man’s sperm and then carried in the womb of the surrogate. Once the baby is born the mother of the egg will claim no right Islamically over the child.
While this article does not intend to discuss the issue of legitimate motherhood, it does intend to discuss who a father is, according to the sharī’ah. There are number of possibilities for the definition of a father. He can be either the biological father whose sperm fertilised the egg, or one who has taken care of the child from a very young age or the one who was married to the mother when she became pregnant with this child. According to Islamic sharī’ah, your father is the man to whom your mother was married when she became pregnant with you. The following story explains the Islamic view concerning the definition of the father.
Sa’d b. Abi Waqqaas, a companion of the Prophet (peace and blessings be upon him), and ‘Abd b. Zam’ah, another companion, disputed concerning a slave child belonging to Zam’ah, the father of ‘Abd and Sawdah (the wife of the Prophet, peace and blessings be upon him). Sa’d b. Abi Waqqaas said: “O Messenger of Allāh, this is the son of my brother, ‘Utbah b. Abi Waqqaas, who asked me to take care of him because he is his son.”
‘Abd b. Zam’ah said: “This is my brother, O Messenger of Allāh, the son of my father’s slave woman who was born in my father’s bed.”
The Messenger of Allāh (peace and blessings be upon him) saw a clear resemblance in this child to ‘Utbah. But he said: “He is yours, O ‘Abd b. Zam’ah. The child is for the (owner of the) bed.” Then he said to Sawdah bint Zam’ah, his wife, “Observe the hijab when around him, O Sawdah.” 
If the child was born in the marital bed, he is to be attributed to the husband, and he cannot be regarded as not being his child except by means of lī’ān  (marriage annulment by means of invoking a curse) where the husband engages in lī’ān with his wife and denies that the child is his.
It is clear from this hadith that the child (about whom there was a dispute) bore a clear resemblance to ‘Utbah b. Abi Waqqaas. Moreover, ‘Utbah b. Abi Waqqaas admitted to his brother Sa’d b. Abi Waqqaas that he had sexual relations with the female slave and causing her to become pregnant and thus the child, biologically, was most likely his. However, the Prophet attributed the child to ‘Abd b. Zam’ah who was the owner of the bed (sharing a legitimate bed with the mother) at that time. This is clear evidence that Islamic sharī’ah defines the father as the one whom owns the bed, or is in wedlock with the mother when she becomes pregnant, regardless of whether he is the biological father or not. The owner of the bed is either the husband or the legitimate slave’s owner.
What about DNA testing deciding the matter?
Many people ask about the relationship between Islam and science – of course there are many Quranic verses that encourage Muslims to reflect and think about the creation of Allāh. For example, Allāh says,
“In the creation of the heavens and the earth and the alternation of the night and day are signs for those of understanding.” 
Such reflection and thinking entails that humans are encouraged to explore the Divine laws of the Creator in an attempt to glorify Him and submit to His majesty and power. However, Allāh occasionally commands us to follow certain methods and guidelines that take into consideration non-scientific aspects when finalising a judgment. Allāh, the Creator, the all-knowing and all-acquainted, knows every aspect of his Creation and wants goodness for them that some individuals, at certain times or places, might not comprehend or be aware of.
There are other similar cases where the Islamic sharī’ah differentiates between sharī’ah definitions and scientific ones. For example, what is najis is defined according to the sharī’ah; otherwise, many items around us would be considered najis according to scientific/chemical definitions. We know that some people do not wash their hands after using the toilet and hence numerous studies report the existence of microscopic traces of urine and faeces on door handles, telephones, food in fast-food restaurants, and so on , but they are not necessarily treated as najis Islamically.
Similarly, the start of the lunar month is confirmed according to the testimony of one who sights the moon with the naked eye. This is the shar’ī month, yet the scientific notion of a month does not accept any sighting and instead a long scientific process has to be followed before concluding the start of a new lunar month; in other words the shar’ī month was not necessarily intended by Allāh to be the same as the astronomical month. It was narrated by ‘Abdullāh b. ‘Abbās that a Bedouin came to the Prophet (peace and blessings be upon him) and said: “I have sighted the moon.” Al-Hasan added in his version: “that is, of Ramadān.” He asked: “Do you testify that there is no God but Allāh?” He replied: “Yes.” He again asked: “Do you testify that Muhammad is the Messenger of Allāh?” He replied: “Yes,” and he testified that he had sighted the moon. He said: “Bilal, announce to the people that they must fast tomorrow.” 
This differentiation also helps us to understand the relationship between science and the Islamic sharī’ah where the Muslim will not find himself in a position where he needs to justify his Dīn or feel inferior to science or other cultures’ values.
The real believer is the one who submits to the Will of Allāh in all matters and is confident that whatever Allāh decides is best for humanity, even if we are unable to perceive it. Allāh says,
“The only statement of the [true] believers is when they are called to Allāh and His Messenger to judge between them they say, “We hear and we obey.” And those are the successful.” 
We must remember that the sharī’ah, the law of Allāh, runs people’s lives in an attempt to establish the Glory of the Creator, first and foremost. Once glory is established, other aims of sharī’ah will be achieved. Those include the stability of society by protecting its inhabitants’ lives, wealth and honour. Taking care of the wellbeing of all members of society as well as their emotions is an intrinsic element of sharī’ah. It also includes protecting the financial properties of those inhabitants. Allāh says in the Qur’ān,
“Allāh desires ease for you and does not desire hardship”
By considering the father as the one wed to the mother, many social and emotional problems can be solved. The child, its welfare, and its future, is the first and foremost party to benefit from the legislation. We have to remember that the child is innocent and has nothing to do with what the elders have done. Therefore, he or she deserves a dignified life. They should be looked after in a healthy and stable environment and receive care similar to that which other children receive, otherwise they will feel different to other members of society which will eventually cause them much stress and psychological problems. Soon after, they could adopt a resentful attitude towards their society where they have received unfair treatment. It is less surprising therefore to read statistics like children from broken homes being nine times more likely to commit crimes, or that the breakdown of marriage is claimed to cost Britain up to a staggering £100 billion per year .
If the married lady was raped and became pregnant then the child is hers and it takes the lineage of her husband. The child will then live a normal life and will be part of that family. The husband can only object to this and refuse to attribute this child to him through an Islamic judicial process though lī’ān. Thinking about all other possibilities of dealing with the child confirms that the method of the sharī’ah is the best, safest and most practical one for the child and for the whole society.
Among the other main benefits of this legislation is more social stability between married couples. In this day in age where promiscuity is common, cheating between spouses has also become a more frequent problem. Consequently, accusations of illegitimate sexual relations and illegitimate pregnancies are also numerous. Many husbands could easily accuse their wives of such relations and ask them frequently to carry DNA tests for their children. Even when DNA results show the children are legitimate, it still leaves unhealed wounds in the wife’s heart and ultimately in her relationship with her husband. However, if the husband knew that he could not easily accuse his wife of infidelity, having to go through the lī’ān process thus dissolving the marriage, he would hardly ever think of accusing her of zina.
In a PhD study carried out in the United Arab Emirates, a researcher carried out a survey in UAE courts and he found that during the years 2001 and 2002 there was no registration of any lī’ān case. This means that there was no request of denying the lineage of any child. However, after DNA testing was introduced by the UAE courts as a means of confirming lineage, he observed a surge in requests to enquire of the lineage of children in approximately thirty cases. He also observed similar trends in Cairo. 
It is this Islamic sharia that was revealed to humanity for their best interest in both lives,
“But whosoever turns away from My Reminder (i.e. neither believes in this Qur’ān nor acts on its orders, etc.) verily, for him is a life of hardship, and We shall raise him up blind on the Day of Resurrection.” 
Notes Al-Qur’ān 58:2  Recorded by Bukhāri and Muslim  Lī’ān is a process in which the husband accusing his wife of infidelity has to take his wife to an Islamic court and swears 4 times that his wife committed zina and the fifth oath is accompanied by invoking the curse of Allāh upon him if he is lying in this accusation. The wife will either accept his accusation or deny it. If she accepts it, she has to be punished otherwise she will be saved from it. In either case, the marriage is dissolved forever and the child, if any, will not be attributed legally to the husband.  Al-Qur’ān 3:190  http://www.today.com/id/21423163/ns/today-today_health/t/soap-germiest-places-your-life/#.U6G2Xo1dXir  Abū Dāwūd  Al-Qur’ān 24:51  Al-Qur’ān 2:185  http://www.telegraph.co.uk/news/politics/8109184/Children-from-broken-homes-nine-times-more-likely-to-commit-crimes.html  See al-Basmah al-wīrāthiyyah wa atharuha ‘alā al-ahkām al-fiqhiyyah by Kalifah al-Baabi p 509-510.  Al-Qur’ān 20:124