Marriage, the Family and Sexuality
The Family in Religious Thought
The family is central to most religious traditions. Christians generally regard the family as a gift from God: the place where children are nurtured in faith, where love is practised, and where society is built from the ground up. The Catechism of the Catholic Church describes the family as “the domestic church” — a community of grace and prayer.
Within Islam, the family is equally foundational. Muslim teaching holds that a strong family is the cornerstone of the ummah (community of believers). Children born into a Muslim family are considered to start life in a state of natural goodness (fitrah), and parents bear responsibility for passing on faith and moral values. Non-religious perspectives, including humanist thought, also value the family highly but tend to ground this in the wellbeing of individuals rather than divine command — the family matters because it supports human flourishing, not because God ordained it.
Genesis 2:22–25 describes God creating woman as a companion for man and the two becoming “one flesh.” Most traditional Christians read this as defining marriage as a lifelong union between a man and a woman, established by God before any human law.
Religious Attitudes to Marriage
Marriage is treated as a sacred institution in both Christianity and Islam. For most Christians, the purposes of marriage include mutual companionship and support, sexual union within a committed relationship, and the procreation and upbringing of children. The Catholic Church regards marriage as a sacrament — an outward sign of God’s grace — and therefore indissoluble (it cannot be ended by divorce, though annulment is possible in certain circumstances).
Jesus affirmed the permanence of marriage in Matthew 19:4–6: “What God has joined together, let no one separate.” This passage is foundational for most Christian teaching on marriage. Many Protestant denominations, while valuing marriage highly, do not classify it as a sacrament and allow for divorce and remarriage in cases of breakdown.
In Islam, marriage (nikah) is a serious legal and moral contract (aqd). It is strongly encouraged: the Prophet Muhammad is reported to have said that marriage is half of one’s religion. The marriage contract specifies rights and responsibilities for both spouses, including the payment of a mahr (gift from husband to wife). Polygyny (a man marrying up to four wives) is permitted under strict conditions, including the requirement of justice and equal treatment. This sharply distinguishes Islamic marriage law from the Christian ideal of monogamy.
The Marriage Ceremony
The Christian marriage ceremony typically involves the couple making vows of lifelong commitment, an exchange of rings, readings from scripture, prayers and a blessing. In a Catholic Mass-wedding, the Eucharist is also celebrated. Different denominations vary in their emphasis: Quakers allow couples to speak their own vows in a meeting for worship; Anglican and Catholic ceremonies follow set liturgical forms. The ceremony is understood to reflect the couple’s covenant with each other and with God.
An Islamic nikah ceremony requires the consent of both parties, the presence of witnesses, the setting of the mahr, and an offer and acceptance (ijab and qubul) witnessed by those present. There is no religious requirement for the ceremony to take place in a mosque. The simplicity of the Islamic ceremony contrasts with the elaborate liturgical forms of some Christian traditions.
The legalisation of same-sex marriage in England and Wales in 2014 has produced sharp disagreement within and between religious communities. The Roman Catholic Church and most conservative evangelical Protestant churches hold that marriage is by definition between a man and a woman, grounding this in Genesis 2 and Matthew 19:4–6. They distinguish this from hostility to gay people: many such churches affirm the dignity of LGBTQ+ individuals while maintaining a traditional definition of marriage.
By contrast, several Protestant denominations — including the United Reformed Church and the Quakers — have voted to allow same-sex marriages within their traditions, arguing that the core Christian values of love, commitment and faithfulness apply equally to same-sex couples. They point to the command in 1 Corinthians 13 to make love the guiding principle and challenge readings of scripture that they consider culturally conditioned rather than eternally binding.
The Church of England’s position is that marriage is between a man and a woman; same-sex couples may receive blessings but not a marriage service. This represents a middle position that continues to be debated internally. In Islam, same-sex relationships are generally held to be forbidden by the majority of scholars, based on Qur’anic teaching and classical jurisprudence, though some progressive Muslim voices argue for reinterpretation.
Non-religious perspectives tend to affirm same-sex marriage on the grounds of equality, personal autonomy and the absence of harm to others. The British Humanist Association actively supported the 2013 Marriage (Same Sex Couples) Act. In England and Wales, a civil partnership was available to same-sex couples from 2005 as a legally recognised alternative to marriage; since 2019 it has also been available to opposite-sex couples. Many religious groups distinguish between civil partnerships (which they may accept as a civil matter) and religious same-sex marriage (which most still decline to conduct).
Cohabitation, Pre-Marital Sex and Celibacy
Muslim attitudes towards the family and marriage are distinctive: Islam treats marriage (nikah) as a near-universal religious duty, the family as the bedrock of the ummah, and the roles of spouses as complementary but distinct. These attitudes sit alongside Christian teaching as the second major religious lens throughout this lesson.
Cohabitation has become the norm for many couples in contemporary Britain before or instead of marriage. Traditional Christian teaching holds that sexual relationships belong within marriage: the body is described as the “temple of the Holy Spirit” (1 Corinthians 6:19) and sexual union is reserved for the marriage covenant. Most Catholic and evangelical teaching therefore discourages pre-marital sex and cohabitation, viewing them as departures from God’s design.
More liberal Christian voices argue that stable, faithful, loving cohabitation shares the moral substance of marriage even without the ceremony, and that the church’s concern should be the quality of the relationship rather than its legal status. Many argue that blanket condemnation of cohabiting couples is pastorally harmful and socially outdated.
Islam similarly holds that sexual relations are only permitted within marriage. There is no concept of cohabitation as a morally acceptable alternative to nikah. Pre-marital sex is strongly prohibited, and modesty in dress and conduct (haya) is emphasised for both men and women.
Celibacy is valued in certain Christian contexts: Catholic priests and members of religious orders take vows of celibacy, following the example of Jesus and Paul (who wrote in 1 Corinthians 7:8 that the unmarried state could be a gift). This is not a universal Christian view — Protestant clergy marry freely. Islam does not regard celibacy as spiritually superior; marriage is seen as completing one’s religious life.
Mark 10:11–12 records Jesus saying that whoever divorces their spouse and marries another commits adultery. This passage, alongside Matthew 19:4–6 and 1 Corinthians 7:10–11, forms the scriptural bedrock for Catholic and conservative Protestant opposition to divorce and remarriage — and by extension shapes their understanding of what marriage fundamentally is.
Contraception is one of the most divisive issues in Christian ethics. The Roman Catholic Church, in the 1968 encyclical Humanae Vitae, reaffirmed that artificial contraception is morally impermissible because every sexual act must remain open to the possibility of new life. Only Natural Family Planning (NFP) — abstaining from sex during fertile periods — is permitted. The reasoning is that sexual union has two inseparable purposes: unitive (deepening love) and procreative (open to life). Separating these, the Church argues, contradicts the nature of marriage.
Most Protestant denominations accept artificial contraception, viewing responsible family planning as consistent with good stewardship and care for existing children and the couple’s wellbeing. They do not find scriptural warrant for an absolute prohibition, and argue that the purposes of marriage include companionship and love as ends in themselves, not only procreation.
In Islam, the majority position permits contraception for valid reasons — spacing births, protecting the mother’s health, or avoiding hardship — though permanent sterilisation without medical necessity is generally discouraged. Non-religious perspectives support access to contraception as a matter of bodily autonomy and reproductive freedom, vital to gender equality.
Fidelity, Sexuality and Non-Religious Views
Fidelity is upheld across religious traditions as essential to the integrity of marriage. The prohibition on adultery appears in the Ten Commandments (Exodus 20:14) and is reinforced in both Christian and Islamic teaching. Religious thinkers argue that fidelity reflects the covenant character of marriage: just as God remains faithful to humanity, spouses are called to remain faithful to each other.
Understanding of sexuality has shifted considerably in contemporary society. Many religious traditions distinguish between orientation (which may not be chosen) and sexual behaviour (which is a moral matter). The mainstream Catholic and evangelical Protestant position accepts that same-sex attraction may not be chosen but maintains that same-sex sexual behaviour falls outside God’s design. More progressive churches affirm same-sex relationships fully, reading the biblical texts on homosexuality as addressing specific cultural abuses rather than committed same-sex relationships.
Humanist and non-religious ethics tend to judge sexual relationships by the standards of consent, honesty and mutual care rather than by religious definitions of permitted and forbidden. On this view, the ethical mode of any relationship — whether heterosexual or same-sex, married or not — is determined by how the people involved treat each other, not by its form.