A quick, but important caveat: I teach at a denominational seminary, was ordained into and serve in a denomination, and not only take seriously, but take pride in, my Lutheran identity and heritage. Whether that makes you want to take more seriously or dismiss altogether my feelings about denominations is, of course, for you to decide.
With that in mind, here are my five chief reasons I not only think the day of denominations has passed but also can't seem to find it in me to shed many tears about it.
1) Denominations are confusing in a post-Christian world and often an impediment to mission. When the larger culture was nominally Christian, we had the luxury of squaring off behind our denominational identities. No longer. Ask the typical person with little or no familiarity with the Christian faith the difference between Methodists, Lutherans, and Presbyterians and she'll likely give you a blank stare that indicates she's wondering whether you're still talking about Christianity. Here's the sad truth: most people in the various denominations have little sense what they mean and no one outside them really cares.
2) The differences between the major denominations are relatively minor. As much as I love a good real-presence vs. memorial-feast slugfest or round of justification/sanctification truth-or-dare, the truth is most of the denominational differences are not only unintelligible to their own members but, in the larger scheme of things, relatively minor. Across the board the major Protestant denominations share a biblical canon, confess the major ecumenical creeds, and observe the same two sacraments. I therefore can - and regularly do - worship at churches of any of the major denominations and feel not even a quiver in my theological conscience.
3) Inordinate amounts of funding are spent on maintaining denominational structures and bureaucracies, money that could be spent on mission. Even though every denomination I know has in recent years cut way back on spending, eliminated various divisions or boards, or extended the times between major assemblies or conventions, denominations are still expending vast sums of money to prop up dated denominational bureaucracies. Would it not make sense to conserve resources by efficiently combining structures? Are seven or eight struggling denominational publishing houses better than one robust one? Where there are three beleaguered denominational seminaries in a single region, might not one healthy pan-denominational school suffice? (And we haven't even started on congregations!) Think of what might happen if the savings were channeled to funding creative media campaigns that didn't extol the virtues of one denomination but taught the Christian faith.
4) Political differences outstripped theological ones decades ago. Let's face it: progressive Lutheran, Presbyterian, and Episcopalian congregations have a lot more in common than do progressive and conservative congregations in the same tradition. Differences over how to read the Bible, the nature of the atonement, and the character of God are far more important today than nuanced differences in polity or regarding the sacraments.
5) Denominational affiliation often represents the triumph of ethnic and cultural loyalties over theological convictions. While denominations my have initially arisen over theological differences, they were soon co-opted by the political realities of their sponsoring state. Little wonder, then, that ethnic and cultural identity are closely tied to denominational affiliation. Those in the club, after all, talk not simply of Presbyterians and Lutherans but ScotchPresbyterians and Swedish or German Lutherans. This has always made it difficult to reach beyond one's ethnic enclave because interested seekers, even if they were attracted to, for instance, Lutheran theology, had to accept it in the form of German chorales or Swedish traditions. Moreover, as ethnic culture has declined as an important identity-maker, so also has religious affiliation - after all, for many folks, if Lutheranism isn't about Santa Lucia, what is it about? And if they've stopped going to the Santa Lucia festival, why bother with church?
Bottom line: while I love my denominational heritage and am all for a robust theological identity and spirited theological conversation, I'd give up denominational identity and structure in a heartbeat if it meant a more unified, comprehensible, and compelling witness to the Gospel. How do we move in this direction? To tell you the truth, I haven't the foggiest idea. (I know that I don't think non-denominational churches are the answer, as they've essentially become denominations minus any sense of organization.) Do I even think it's possible, given how much we have invested in our denominations and the good work they still accomplish? Again, you've got me. But I do know it's time to raise these questions and initiate a conversation about mutual collaboration and mission that runs far beyond anything our parents or grandparents would have dreamed possible.