We continue our series on the meaning of marriage with another point of view. Though most evangelicals oppose same-sex marriage, they do not necessarily agree about how exactly to oppose it or how strongly to work against it. Here Daniel A. Crane, assistant professor of law at Benjamin N. Cardozo School of Law at Yeshiva University in New York City, explains his concerns regarding this issue.
   —Editors

With same-sex marriage licenses pouring out of City Hall in San Francisco before they were declared invalid, state courts inundated with claims of entitlement to same-sex marriage, a federal constitutional amendment proposed to define marriage as a heterosexual union, and the presidential candidates trying to mollify as many constituencies as possible on this hot potato, same-sex marriage certainly has our attention. Indeed, it's becoming a shibboleth.

A shibboleth is a single issue by which a political candidate or party is judged. The word comes from the biblical story of Jephthah and the Gileadites in Judges 12:4-6. Jephthah had routed Israel's foes from Ephraim and was determined to cut them down to the last man. The Ephraimites weren't obviously distinguishable from the Gileadites by physical appearance, and some tried to sneak through Jephthah's lines. So Jephthah devised a clever test: Any man trying to ford the Jordan was required to say the Hebrew word shibboleth, which means "a torrent of water." Since the Ephraimites mispronounced the word as sibboleth, they were easily identified and slaughtered.

When it comes to politics, we evangelicals love our shibboleths. There is a certain convenience in evaluating political candidates, organizations, and movements by their stand on some discrete social issue—think ...