Jonathan AC Brown is the Alwaleed bin Talal chair of Islamic Civilization in the School of Foreign Service at Georgetown U., and associate director of the Alwaleed bin Talal Center for Muslim Christian Understanding. His books include “Misquoting Muhammad: The Challenge and Choices of Interpreting the Prophet’s Legacy” (Oneworld, 2014).

I’ll be conservative: There is a lot of misinformation about Islam in the media. A religion of some 1.5 billion people around the world, people who wake up every morning to the same hopes and anxieties as Americans, is boiled down to images of barbarity.

I sometimes tell my students that Islam is Judaism Redux — bigger cast, bigger budget. Like Judaism, questions of right and wrong are conceived of more in the idiom of law than in a more abstract sense of principles. Like Judaism, Islamic law (Shariah) has been developed by a clerical class that has always been more scholars than priests. Like Judaism, these Muslim scholars (ulama) have derived the Shariah from a core written revelation, the Quran (analogous to the Torah of Moses), read through the prism of an originally oral scripture, the Prophet Muhammad’s precedent (analogous to the oral Torah inherited by the rabbis), a process added to and influenced by the ulama’s own methods of reasoning, interpretation and their cultural assumptions.

Also like Judaism, the Shariah is first and foremost concerned with questions of proper worship, ritual purity, prohibited or permitted foods, sacred times and sacred places. Only then does it expand to encompass areas like contracts, property, marriage, inheritance, civil and criminal law.

When looking at the issue of gay marriage, two main features of the Shariah are most pertinent. First, the Shariah is law. It is concerned primarily with actions as opposed to emotions or wishes. Second, marriage in the Shariah is not a sacrament. Stripped of all the cultural accretions Muslims have added on, and minus the obviously crucial elements of love and companionship, marriage is nothing more than — literally — a contract between a man and a woman in which the man provides the woman with financial support in return for exclusive sexual access. It’s a contract that makes sex and reproduction legal in the eyes of God and legitimate in the eyes of society. Since marriage is a contract premised on vaginal intercourse and financial obligation between a man and a woman, same-sex couples could not engage in one. They could construct an arrangement for inheritance and shared property that mimicked marriage, but it would not be marriage.

The focus on actions in the Shariah means that desires or inclinations have no legal substance. The Shariah doesn’t have a position on homosexual desire. Indeed, it can be quite normal. Like ancient Athenians, classical Muslim scholars and litterateurs regularly marveled over the beauty of young boys. Heirs to the Greeks, Muslim scholars found it expectable that men would be attracted to young boys or beautiful males, since they manifested the same feminine beauty as women. Many Muslim scholars even prohibited men from gazing at beautiful young boys, and encouraged parents to dress such children in veils when in public.

But the Shariah does have a clear position on sexual acts. All sexual contact between unmarried men and women is forbidden. Sexual contact less than vaginal intercourse is punishable by the judge’s discretion. Based on the Quran, vaginal intercourse between an unmarried couple is punishable with 100 lashes.

The Quran deals explicitly with Sodomy (Liwat, named after Lot and his people). The holy book recounts the story of Sodom several times, condemning its people’s overall immorality, and specifically criticizing its men for “going to men out of desire instead of to women.” Sodomy, understood as anal sex, was thus prohibited by the consensus of Muslim scholars (Muhammad’s condemnation of anal sex with wives added hetero anal sex to this as well). Muslim scholars set the punishment for anal sex between men as anywhere from a relatively light one at the judge’s discretion (since Sodomy could not result in illegitimate children), to the same punishment as fornication (based on analogy to hetero-sex), to execution (based on a command from Muhammad of disputed authenticity).

Because sexual contact between women does not involve penetration with a penis, it never received the same legal categorization as Liwat. Called Sihaq (‘grinding’), it was prohibited under the general rule against sexual contact outside marriage.

The issue of gay marriage in America is a tough one for Muslims. On one hand, it’s nigh impossible to construct an argument by which sexual contact between men, let alone anal sex, is considered permissible in God’s eyes. On the other hand, attempts to ban the Shariah in the U.S. threaten Muslims’ ability to have their own marriage contracts. Like gays, they want to be able to define marriage free from majoritarian cultural biases. So many Muslims are willing to support the rights of other Americans to shape marriage according to their particular beliefs. Muslims expect their beliefs and relationships to be respected in return.