In the classical law of slavery, yes: Islamic law recognized concubinage with a female slave whom a man lawfully and exclusively owned, when no legal impediment existed. That was a rule within the historical institution of slavery. It was not a permission to approach servants, employees, prisoners, trafficked women, refugees, or any vulnerable person, and it was not a license for kidnapping, prostitution, humiliation, injury, or abuse.

Are concubines allowed in Islam?

The Quranic texts, as understood by the classical jurists, recognized lawful sexual relations through marriage and, for male owners, through ma malakat aymanukum - "those whom your right hands possess."

"And those who guard their private parts except from their spouses or those whom their right hands possess, for indeed they are not to be blamed."

Quran 23:5-6

The same wording appears in Quran 70:29-30, and Quran 4:24 also discusses this category in the context of prohibited women. In this legal usage, ma malakat aymanukum referred to slaves under the historical law of slavery, not to employees, servants, or people over whom someone merely has power. A female slave in such a relationship is commonly called a concubine.

Therefore, the historically accurate answer is that classical Islamic law allowed concubinage. It did not require a separate marriage contract, and the four-wife limit applied to wives, not to concubines. This permission, however, operated inside a defined legal institution and was subject to rules governing ownership, prohibited kinship, fosterage and affinity, pregnancy, parentage, maintenance, and treatment.

It was a specific legal status, not access to vulnerable women

A man could not have relations with any woman merely because she was socially weak, captured, employed by him, indebted to him, or under his authority. Classical law required lawful and exclusive ownership. Someone else's slave was forbidden to him, and he could not have intercourse with a jointly owned slave because he did not own her entirely. The normal prohibitions of lineage, fosterage, and affinity applied, and an istibra waiting period was required before relations could begin, to establish that the womb was clear and to protect lineage.

A captive did not automatically become the private possession of an individual soldier. Captives fell under public authority and could not simply be seized, hidden, distributed privately, or treated as available for intimacy. Nor did Islam permit kidnapping or the enslavement of a free person. In a hadith qudsi, the Prophet (PBUH) reported:

"Allah says: I will be an opponent to three on the Day of Resurrection... a man who sells a free person and consumes his price."

Sahih al-Bukhari 2227

The basic point is clear: physical control is not ownership, and power over another person does not make that person sexually lawful.

Abuse, coercion, and what must be admitted

Historical accuracy requires precision. Classical jurists did not treat concubinage as marriage, did not require a nikah contract for it, and did not formulate the ruling in the modern language of affirmative sexual consent. These facts should not be hidden.

But it is equally false to turn this into a general permission for rape, assault, humiliation, prostitution, or sexual predation against any woman a man can dominate. Islamic law did not erase the humanity of enslaved people or remove the owner's duties toward them. The Prophet (PBUH) said:

"Your slaves are your brothers whom Allah has placed under your authority. So whoever has his brother under his authority, let him feed him from what he eats and clothe him from what he wears. Do not burden them with what overpowers them; and if you burden them, then help them."

Sahih al-Bukhari 30; Sahih Muslim 1661a

The Quran also explicitly prohibited forcing enslaved women into prostitution:

"Do not compel your slave girls to prostitution, if they desire chastity, seeking the temporary interests of worldly life. And if someone compels them, then after their compulsion Allah is Forgiving and Merciful."

Quran 24:33

The phrase "if they desire chastity" describes the case being condemned; it is not permission to exploit them when that phrase is absent. The final clause refers to Allah's forgiveness and mercy for the coerced women after they were compelled, not to a license for the coercers. Prostitution, sexual exploitation, physical harm, and oppression remain forbidden.

So the precise answer is this: classical law did permit intercourse through lawful milk al-yamin, but it did not permit kidnapping free women, assaulting captives at will, using servants or employees, accessing another person's slave, forcing prostitution, or treating enslaved people as outside the protection of Islamic moral and legal duties.

Was the number of concubines limited?

The four-wife limit in Quran 4:3 applied to wives, not concubines. Classical Sunni law did not state an equivalent fixed numerical maximum for female slaves lawfully owned by a man. On that narrow point, the critic is correct.

But "no fixed numerical maximum" did not mean access to any number of women one could overpower. Each case still depended on the required legal status: lawful and exclusive ownership, absence of kinship or other legal barriers, observance of istibra, maintenance, humane treatment, and protection of lineage.

If a concubine bore her owner a child whose paternity was legally established as his, the child was free, legitimate, and attributed to the father. She became known as an umm al-walad. Under the settled Sunni ruling, she could not be sold and became free upon the owner's death, although some early authorities differed over details before that ruling became established.

Does this include domestic workers today?

No. A domestic worker is a free employee, not "one whom the right hand possesses." Employment, sponsorship, debt, poverty, immigration control, or living in someone's house does not create ownership and does not make sexual relations lawful.

Nor can the status of milk al-yamin be created today by kidnapping, trafficking, prison control, civil war, or private armed groups. In the modern world, states and peoples are bound by covenants, laws, and treaties that abolish slavery and protect prisoners and civilians. Muslims are commanded to honor binding covenants:

"O you who believe, fulfill the contracts."

Quran 5:1

Relations with a domestic worker outside a valid marriage are zina and forbidden. Coercing or abusing her adds oppression and criminal violence to that sin. The same applies to prisoners, trafficking victims, refugees, and other vulnerable women: none becomes a concubine merely because another person has power over her.

Conclusion

Concubinage was permitted in classical Islamic law within the historical institution of lawful slavery. It did not require a marriage contract, and the four-wife limit did not apply. But it was never a general permission to have relations with servants, employees, captives at will, trafficked women, or anyone vulnerable. It required a specific and exclusive legal status and remained subject to rules protecting lineage, maintenance, humane treatment, and freedom from harm and exploitation.

Accordingly, no one may use the verses about "those whom your right hands possess" to justify relations with domestic workers, prisoners, trafficked women, or anyone else who is free. Employment, captivity, poverty, and physical control never make another human being sexually lawful.

For the fuller historical and legal discussion, see Can You Be Intimate with Slaves? and Islam's Perspective on Slavery.