Concubinage is an interpersonal relationship in which a person engages in an ongoing sexual relationship with another person to whom they are not or cannot be married to the full extent of the local meaning of marriage. The inability to marry may be due to multiple factors such as differences in social rank status, an existent marriage, religious prohibitions, professional ones (for example Roman soldiers) or a lack of recognition by appropriate authorities. The woman in such a relationship is referred to as a concubine.
The prevalence of concubinage and the status of rights and expectations of a concubine have varied between cultures as well as the rights of children of a concubine. Whatever the status and rights of the concubine, they were always inferior to those of the wife, and typically neither she nor her children had rights of inheritance. Historically, concubinage was frequently entered into voluntarily (by the woman or her family) as it provided a measure of economic security for the woman involved. Involuntary or servile concubinage sometimes involved sexual slavery of one member of the relationship, usually the woman. Unlike ancient cultures, Christian Europe opposed concubinage, regarding any sexual relations outside of a monogamous marriage as sinful. Nevertheless, sexual relations outside marriage was not uncommon, especially among royalty and nobility, and the woman in such relationships was commonly described as a mistress. However, the children of such relationships were counted as illegitimate and were barred from inheriting the father's title or estates, even when there was an absence of any legitimate heirs.
While various forms of long-term sexual relationships and co-habitation short of marriage have become increasingly common in the Western world, these are generally not described as concubinage. The terms concubinage and concubine are used today primarily when referring to non-marital partnerships of earlier eras. In modern usage, a non-marital domestic relationship is commonly referred to as co-habitation (or similar terms), and the woman in such a relationship is generally referred to as a girlfriend, lover or (life) partner.
Female slave who functioned as a secondary wife and surrogate mother. The Hebrew word for concubine is a non-Semitic loanword borrowed to refer to a phenomenon not indigenous to Israel. Babylonian and Assyrian law codes regulate primary and secondary marriages more specifically than do the Old Testament laws. Exodus 21:7-10 has been appealed to as regulative of some aspects of concubinage, but that only implicitly.
Concubines are mentioned primarily in early Israelite history during patriarchal times, the period of the judges, and the early monarchy although some later kings also had concubines. While concubines did not have the same status as wives, they were not to be mistreated ( Exod 21:7-10 ) nor could they be violated by other males ( Gen 35:22 ) with impunity ( Gen 49:3-4 ). They seem to have received higher status if they bore sons, or at least they are remembered by name ( Gen 21:10 ; 22:24 ; 30:3 ; 36:12 ).
The sons of some concubines were treated as co-heirs with the sons of wives. Was this facilitated by the wife accepting and naming the child as her own, or was the father's act of "adopting" the son required? Paucity of information prevents us from answering this definitively. In at least one case the inheritance potential of the concubine's son seems to present a threat to the primary wife and her son ( Gen 21:10 ). Abraham eventually gives the full inheritance to Isaac, and only gives gifts to his concubines' sons ( Gen 25:6 ).
The story of Judges 19-20 suggests that the terminology used of relationships in a regular marriage are also used in a concubinage relationship. The man is called the concubine's "husband" ( 19:3 ; 20:4 ) and the woman's father is referred to as the man's "father-in-law" ( 19:9 ). Some evidence suggests that royal wives (concubines?) were inherited by succeeding kings ( 1 Sam 12:8 ). Thus approaching the royal concubines ( 1 Sam 16:21-22 ) or even requesting the king's female attendant for a wife ( 1 Kings 2:13-22 ) can be understood as the act of one attempting to take the throne away from its designated occupant ( 1 Kings 2:22 ).
The practice of taking concubines as "wife" was used to provide a male heir for a barren wife (cf. Gen. 16, 35, 36). In addition, the practice provided a social safety net for poor families who could sell their daughters in dire times ( Exod 21:7-10 ; Judges 19:1 ). It seems plausible to suggest that the practice of taking concubines was perpetuated to meet the sexual desires of the males and/or to cement political alliances between nations. Nevertheless, the paucity of sufficient internal data requires dependence on comparative ancient Near Eastern evidence for these conclusions. Multiplying children through concubines would not normally complicate the inheritance lines, but would increase the available family workforce and the family wealth.