Religion and sexuality
Views on sexual morality vary greatly over time and from culture to culture. As with any other type of morality, social and environmental conditions play a part in the development of a given society's most commonly held views on sexual morality.
Debate
In Western pluralistic societies of the 20th and 21st centuries, there often exists debate on not only whether there is a common morality, but on whether it is right to expect such a common view. In most western societies, laws allowing a wide range of sexual relationships between consenting adults is the norm, although that legal range varies from jurisdiction to jurisdiction. The debate thus often includes a sub-argument of what is legal vs. what is moral.
Historical views
In previous centuries and in many non-western cultures of the 20th and 21st centuries, there has been less room for debate. This does not mean, however, that views on sexual morality have ever been homogenous. For example, in Hellenic society, homosexuality was often encouraged and accepted as part of the socialization and upbringing of young men, especially those in the military. These relationships were in addition to heterosexual relationships entered into for the establishment of families and the production of progeny so that property would be inherited and kept within a larger kinship group. The importance of the kin-group and the maintanence of its property was such that, under certain circumstances, Athenian law allowed an uncle to marry his neice in order to keep family property together.
Needs more on other cultures and times
In the United States, what many conservatives call "traditional morality" is held to prohibit all extramarital sex, because of the moral belief that sexual relations should occur only between husband and wife. This view of morality thus disapproves of premarital sex, whether between teenagers or adults; adultery; and homosexual relations. These conservatives believe that human beings are capable of abstaining from sex when unmarried or separated from their spouse, a view which some liberals apparently dispute.
Many people, arguably a majority, disagree with this traditional view. Generally they believe that sex, including homosexuality, is a natural behavior which should not be restricted for any reason: especially not by legislation or other imposed moralities. Rather, many of them support educating young people on how to make decisions about sex that will not "compromise" them or others.