“One statistic I saw when writing my book that floored me was that a child living together with unmarried parents in Sweden has a lower chance that his family will disrupt than does a child living with married parents in the U.S.”

“When an institution so central to human experience suddenly changes shape in the space of a generation or two, it’s worth trying to figure out why.”

Belinda Luscombe of TIME magazine made that observation in the course of reporting on a major study of marriage undertaken by TIME and the Pew Research Center. In the cover story for the magazine’s November 29, 2010 edition, Luscombe summarizes their findings with a blunt statement: “What we found is that marriage, whatever its social, spiritual, or symbolic appeal, is in purely practical terms just not as necessary as it used to be.”

Without doubt, marriage has been utterly transformed in the modern world. In Western nations, the concept of marriage as a sacred covenant has given way to the idea that marriage is merely a legal contract. The limitation of sexual intercourse to marriage went the way of the Sexual Revolution, even as the ideal of permanence gave way to no-fault divorce and serial monogamy. And as for monogamy, that may be on shaky ground, too. These days, you can’t take anything for granted.

The debates over the legitimization and legalization of same-sex marriage have, among other things, revealed the fact that far too many Americans (and that includes a frightening number of American Christians) are simply unarmed for any intellectual conflict on any question related to marriage.

And the demographics? Brace yourselves. In 1960, 70 percent of all American adults were married. Now, that number is just over half. Eight times as many children are born out of wedlock as compared to that same year. In the 1960s, two-thirds of all young adults in their twenties were married. Now, only 26 percent of twenty-somethings are married.

Statistics can inform or misinform, and it is possible to find statistical support that puts a happier face on the health of marriage. But in order to find these happier statistics, it is necessary to redefine the question.

For example, some marriage defenders will assert, accurately, that most Americans will at some point be married. But that fact lowers the question of marriage to the minimalist level of “at some point.” By any honest measure, marriage is in big trouble.

When Belinda Luscombe argues that marriage is “in purely practical terms just not as necessary as it used to be,” she has a rationale to back up her argument. “Neither men nor women need to be married to have sex or companionship or professional success or respect or even children.”

All that is true — when marriage is viewed on the canvas of American culture. Marriage no longer regulates sex. The Sexual Revolution severed sex from marriage in a social sense, and the arrival of The Pill offered a pharmaceutical means of severing sex from reproduction. No-fault divorce arrived as a legal accommodation to marital impermanence, effectively redefining both marital and family law in the process.

Social status and professional expectations were liberated from the question of marriage, and many feminists declared that marriage itself was an impediment to the full liberation of women.

And yet, Luscombe ends her argument about the “not as necessary as it used to be” status of marriage with these words — “yet marriage remains revered and desired.”

Really? Well, that all depends on how you define reverence and desire.

TIME reports that 40 percent of Americans believe that marriage is now obsolete, up from 28 percent in 1978. Cohabitation is now the norm for American adults — not just before marriage, but increasingly instead of marriage.

And American cohabitation is an exceedingly weak arrangement. As Andrew Cherlin of Johns Hopkins University explains, Americans “have the shortest cohabiting relationships of any wealthy country in the world.” Less than half of all Americans believe that cohabitation is morally wrong.

Divorce is now an institutionalized part of American life, complete now with an industry putting out divorce announcements, greeting cards, and party plans. The American divorce rate, though now somewhat stable, is so disastrously high that even social scientists are shocked.

As Professor Cherlin remarked: “One statistic I saw when writing my book that floored me was that a child living together with unmarried parents in Sweden has a lower chance that his family will disrupt than does a child living with married parents in the U.S.”

That statistic should floor all of us.

The TIME/Pew study also revealed more visible contours of the “marriage gap” that has emerged with respect to income and education levels. For most of the twentieth century, the age of one’s first marriage rose for those young adults pursuing a college education, while those without a college education married earlier. That is no longer the case. Now, it is those marked by lower incomes and educational levels who are marrying late — if at all. In a stunning reversal of social patterns, it is the more highly educated who are now more likely to marry.

Economic factors are most often cited as the reason for this reversal, but this is not fully convincing. In far more desperate economic times, couples have managed to get married, stay married, and raise a family. Furthermore, as TIME notes, this pattern becomes a formula for disaster, since marriage uniquely provides the stability needed to escape poverty and many social pathologies.

TIME’s cover asks the question straightforwardly — “Who Needs Marriage?” The magazine and its team sought to answer that question “in purely practical terms,” doing their best to leave questions of morality and theology aside.

But Christians, who rightly see the practical benefits of marriage as exemplars of common grace, cannot stop there. We believe that humanity needs marriage. God created the institution of marriage — defined on his terms — as the central institution of human society. Marriage was given to us by our Creator as the central institution for sexual relatedness, procreation, and the nurture of children. But, even beyond these goods, God gave us marriage as an institution central to human happiness and flourishing.

Rightly understood, marriage is essential even to the happiness and flourishing of the unmarried. It is just that central to human existence, and not by accident.

There is much more to the Pew Research Center’s report, but TIME’s cover story put the most crucial questions before its readers. The question on its cover demands a faithful answer.

Who needs marriage? I do. You do. We all do — and for reasons far more fundamental than can be explained “in purely practical terms.”

Dr. R. Albert Mohler, Jr.,serves as president of The Southern Baptist Theological Seminary — the flagship school of the Southern Baptist Convention and one of the largest seminaries in the world. This commentary is taken from his blog at www.albertmohler.com

and is used with his permission.