What keeps prostitution illegal in many parts of the world is that people find it morally objectionable, and what makes prostitution morally objectionable is that sex, according to the religious views of many, is a sacred act, reserved for married couples and should not be bought and sold like any base, man-made creation. How different religions approach the issue varies, but it is almost universally looked down upon.

Prostitution in Islam

The Quran forbids sex out of wedlock, but Surah 4:24 allows for a man to temporarily marry a woman in exchange for mutually agreed upon compensation. The "mutaa," or enjoyment marriage, had long fallen out of fashion in the Middle East until the United States invaded Iraq in 2003. The removal of Saddam Hussein, who had banned the practice, allowed Shiite Muslims, who are more accepting of "mutaa" than are Sunnis, to participate in temporary marriage more freely. The distinctions between a prostitute and a temporary wife may be minimal; a temporary wife won't likely marry several men in the same day, for example, but in all practical terms, it is a way for people to exchange sex for money without the stigma of participating in prostitution. After all, if you're married, it's not a sin.

Prostitution in Christianity

The most famous prostitute in Christianity is probably Mary Magdalene. But was she a prostitute? Throughout history, she's been cast in many roles, but according to a 2006 article in "Smithsonian" magazine by James Carroll, prostitute may be one of the most fallacious. The mistake likely arises from interpretations conflating the story of a repentant prostitute washing Christ's feet at the end of Luke 7 and the introduction of Mary Magdalene at the beginning of Luke 8. Carroll points out these were two different women. Mary Magdalene was actually a prominent figure from whom Christ cast out seven demons.

After the prostitute washes his feet, in Luke 7:37-48, Christ's host inquires as to why He would allow the prostitute to touch him. Jesus replies with a parable about forgiveness, and pardons the woman's sins. While the teachings of Christ focus more on love and forgiveness, it must not be missed that prostitution is certainly a sin.

Prostitution in Judaism

Islamic and Christian views on prostitution and marriage, though different, are both established on the scriptural principles of Judaism. There are well-known prostitutes from the Old Testament; Rahab, who hid Joshua's spies in Jericho, for instance. For her obedience, she was rescued when Jericho fell, and she was adopted into Jewish society. So ancient Judaic society was not entirely uncomfortable with prostitution, but Deuteronomy 23:17-18 forbade harlotry among the people of Israel and the use of wages earned by harlotry as a holy offering.

Hindu Prostitution

Those not familiar with Hinduism might think that because the "Kama Sutra," one of the most well-known and authoritative religious books about human sexuality, is a Hindu text, prostitution would be acceptable, or at least excusable, in Hindu society. Consider, though, the bodily self-denial of leaders like Mahatma Gandhi, and passages from the sacred text known as Bhagavad-Gita, such as, "...those pleasures arising from the senses contacting sense objects are indeed the source of misery only..." Hindus consider the body a sacred temple. Sex for money is seen as a base, immoral pursuit.

Legalization in a Secular World

Religious views on the legalization of prostitution run the gamut from acceptable but discouraged, to outright forbidden. Historically though, people want to have sex, and just like anything else people want, there will always be other people capitalizing on that desire. Some religions dance around it and try to find ways to make it seem less dirty, while others treat it as a natural part of the carnal, mortal world God put us in. Legal or not, though, virtually all theistic religions view prostitution as sin.