Is there a possibility that the Christian Reformed Church in North America and the Reformed Church in America, which split over a century ago, could someday reunite?

A new book, released at the beginning of this month and written appropriately enough by four professors at two colleges closely identified with the denominations, is adding to that conversation.

"Divided By A Common Heritage: The CRC and the RCA at the Beginning of the New Millennium" is authored by Calvin College political scientists Corwin Smidt and Jim Penning, and Hope College sociologists Donald Luidens and Roger Nemeth. It has been published by Eerdmans through the historical series of the Reformed Church in America.

"The impetus for it was the discussion that's begun in the last 10 or so years, rather more aggressively recently, about whether or not the two denominations, in the face of the fact that they're both losing members, should be thinking now about reconciliation, about merging," Luidens said.

The RCA and CRC were originally one denomination, with the CRC splitting away in the 1850s over various doctrinal and social issues. Both denominations grew for many years but since peaking in the 1960s have lost thousands of members. The RCA currently has about 170,000 confirmed members, down from a mid-1960s high of 235,000. Today the CRC numbers 268,000 members, a decline from 272,000 in 1965.

The scholars note that the overall figures hide dramatic regional shifts in both denominations. RCA membership in the Midwest has remained fairly stable during this period, while the number of members living in the eastern United States has dropped dramatically. The shift has reduced the East's share of the RCA's membership to less than a quarter. Likewise, while CRC membership in the United States dropped, the number of Canadian CRC members rose. Canadians now comprise nearly one third of the CRC.

"Much of this discussion," Smidt said, "has to do with the trends and challenges confronting both denominations. These factors include declining and aging memberships (reflecting in part the smaller family size associated with today's family compared to families of a generation or two ago), the lack of significant geographical expansion beyond their historic denominational pockets, and an inability to make substantial inroads among minority ethnic groups in the United States and Canada."

"Divided by a Common Heritage" compiles and culminates research that the two teams of scholars have been conducting on the denominations for decades, including through surveys and historical data. Luidens and Nemeth since 1974 have studied membership trends in the RCA, Hope's parent denomination, while Penning and Smidt have been studying Calvin's parent denomination, the CRC, for more than 20 years.

"Both Corwin and Jim at Calvin and Roger and I have published dozens of articles that have appeared in all kinds of scholarly journals as well as in the 'Church Herald' and 'Banner.' But these articles have provided time-bound, individual snapshots," Luidens said. "This book is the one time when we look at the whole range of our research. This really is in many ways a kind of retrospective on our years of research and an effort to try to contextualize it."

Common characteristics, the scholars note, make the idea of merging tempting. For example, in addition to sharing a Dutch heritage and Reformed theology, the RCA and CRC approach political issues in comparable ways, with pastors using their pulpits to emphasize personal and collective morality rather than to stump for specific candidates or causes. "That's important in this day and age when more churches are taking a more activist role," Nemeth said.

However, the researchers have also found important differences between the CRC and RCA.

For example, they found that while the Midwestern members are similar in outlook in many ways, the denominations differ significantly in other parts of North America. For example, the researchers' surveys have shown that the segment of the RCA based in the East is generally more liberal than other sections of the RCA, while the segment of the CRC in Canada is more conservative than the CRC membership in the Midwest. "These two segments of the RCA and CRC are so different on measures of belief, religious practice and social/political issues that it is hard to imagine them remaining comfortably under one denominational umbrella," Luidens said.

History has played a significant role in the development of the distinct nature of the two denominations, according to the researchers. The RCA began with the settlement of New Amsterdam in the 1600s and had to contend early-on with a diverse population as New Amsterdam was transformed into New York City under the English. The CRC, by contrast, was formed in the Midwest where there was relative homogeneity following the mid-19th century Dutch immigration.

Even the reasons the Dutch settled in the U.S. influenced the regional and denominational character. The colonists in New Amsterdam were primarily motivated by economic opportunity, with religion a part of their lives, while religion itself was a significant motivator for those who settled in the Midwest en masse in the 1800s. The immigrants who founded Holland and Pella, Iowa, for example, were led to North America by their pastors.

The researchers note, however, that the differences between the RCA and CRC needn't preclude working together. For example, as neighboring children of their denominations, Hope and Calvin colleges are often cast as arch-rivals, particularly on the playing field, but through the years have also found ways to work together.

Penning and Smidt and Luidens and Nemeth have long collaborated in that constructive spirit. For example, they have regularly consulted on their research, have co-edited books together, and were among the founders of the International Society for the Study of Reformed Communities and have been involved in the publication of three volumes from the Society's triennial meetings.

The process of writing "Divided by a Common Heritage" mirrors an option that the researchers feel could help the denominations in any case: namely, that the RCA and CRC find ways to cooperate, often through individuals, denominational agencies, and local churches, for their mutual benefit even while remaining independent.

Such cooperation could take the form of congregation-to-congregation communication and joint activity, such as through joint worship services or through working together on CROP Walk or Habitat for Humanity projects.

"Sharing similar locations means that members of one denomination frequently know those of the other, enabling local congregations to cooperate should they desire to do so," Smidt said.

The CRC and RCA could also share ideas with one another based on their individual experiences.

"The issue of declining membership is going to have to be addressed whether the denominations merge or not," Nemeth said. "Maybe this is where they can help each other. Instead of a formal merger, perhaps what can come out of this is that they share their experiences of what makes for a successful congregation or a successful church start."

In the end, opting to cooperate doesn't preclude the possibility of exploring a merger later - it could, Smidt noted, even make the choice clearer.

"The establishment of patterns of cooperation, then the continued expansion of such cooperation, and finally the continually expanding efforts of cooperation as new opportunities become available, set the foundation for what might become the ultimate merger of two denominational bodies," Smidt said.