From the earliest days of the Christian faith, Christians have viewed marriage as a divinely blessed, lifelong, monogamous union between a man and a woman. However, while many Christians might agree with the traditional definition, the terminology and theological views of marriage have varied through time in different countries, and among several Christian denominations.
Roman Catholic and Eastern Orthodox Christians consider marriage as a holy sacrament or sacred mystery, while Protestants consider marriage to be a sacred institution or "holy ordinance" of God. However, there have been differing attitudes among denominations and individual Christians towards not only the concept of Christian marriage, but also concerning divorce, remarriage, gender roles, family authority (the "headship" of the husband), the legal status of married women, birth control, marriageable age, cousin marriage, marriage of in-laws, interfaith marriage, same-sex marriage, and polygamy, among other topics, so that in the 21st century there cannot be said to be a single, uniform, worldwide view of marriage among all who profess to be Christians.
Christian teaching has never held that marriage is necessary for everyone; for many centuries in Western Europe, priestly or monastic celibacy was valued as highly as, if not higher than, marriage. Christians who did not marry were expected to refrain from all sexual activity, as were those who took holy orders or monastic vows.
In some Western countries, a separate and secular civil wedding ceremony is required for recognition by the state, while in other Western countries, couples must merely obtain a marriage license from a local government authority and can be married by Christian or other clergy if they are authorized by law to conduct weddings. In this case, the state recognizes the religious marriage as a civil marriage as well; and Christian couples married in this way have all the rights of civil marriage, including, for example, divorce, even if their church forbids divorce.