With the institution of marriage weakening in American society, Christians are left with three options.

"They can yield to the trends devaluing marriage. Or they can admit defeat in society but try to maintain traditional teachings inside the church. Or they can swim against the current and insist that both church and society lend a hand in strengthening marriage," says Alan Wisdom, vice president for Research and Programs at The Institute on Religion and Democracy.

Wisdom urges Christians to choose the last option.

IRD released a new paper touting the social value of traditional marriage and taking stock of the debate about its future in U.S. society. The paper is part of the Institute's "Mount Nebo" series which offers an overview, "from an orthodox Christian perspective," of public policy issues, and suggestions on how Christians should engage them.

In the 47-page paper, Wisdom contends that marriage is the most basic building block of human society and is established and blessed by God. But over the past two generations, marital patterns have changed and the understanding of marriage has shifted.

Among the trends weakening the marital bond is the "ideal of romantic love" – a love that is all about "two people who love each other."

He argues that romantic love tends to isolate the couple, marginalizing the traditional third parties to the marriage, which include families, the community, the church, the state, and even God himself.

"All are reduced to spectators applauding the all-conquering love of the two," he points out.

Marital relationships, however, are designed to open "a window to understanding both God and humankind."

Another problem posed by romantic notions is that they do not clearly distinguish marriage from other relationships that also involve "two people who love each other."

The wedding ceremony, therefore, becomes a mere formality.

Romantic love also "feeds the recent drive to equate cohabitation and same-sex relationships with marriage," Wisdom contends.

A second trend weakening marriage is rather than looking to God to define their marriage, couples look to the law. Marriage becomes just a legal contract.

"If marriage is just another contract, then there is no necessary reason that it has to be a permanent or total union," he states. "The law increasingly treats the spouses as two autonomous individuals in a temporary and limited partnership. The biblical notion of the two sexes becoming one flesh has retreated from view."

"If marriage is an infinitely flexible contract, then the possibility of marriages joining members of the same sex – or even marriages involving more than two parties – is increasingly plausible."

Statistics show that over the last 40 years, U.S. adults who are married went down from 68 percent in 1960 to 53 percent in 2007. Meanwhile, the proportion of adults who are divorced climbed from two percent to ten percent. And the proportion of Americans who never married (among 30 to 44-year-olds) grew from 7 percent in 1970 to 20 percent in 2005.

The dismal statistics and shifting trends have Wisdom asking, "Is it worth the cost for Christians to continue to defend and promote this embattled institution?"

Before Christians choose to give up on society or even give in, Wisdom points to some positive trends.

Divorce rates have gone down over the past two decades, teenage sexual activity and pregnancies have declined, U.S. voters have upheld the traditional definition of marriage whenever they have been given the opportunity to decide the question (judges, not voters, delivered almost all the victories for same-sex marriage), and the vast majority of U.S. churches hold to a biblical Christian understanding of marriage.

"In short, the battle for marriage is far from over," he highlights.

"The question is whether U.S. Christians are ready to move from a defensive position (defeating efforts to redefine marriage) to a more proactive posture (working together to strengthen marriage)."

IRD's marriage paper is designed for individual or group study as it examines biblical passages and the history of the church's approach to marriage. It also presents social science evidence showing the weakened state of marriage today, but also the benefits that marriage brings for both adults and children.

The first "Mount Nebo" paper addressed stewardship of the Earth.