Ecclesial differences?

I mentioned the Manhattan Declaration last week and wanted to put out a follow-up. At first blush the document seems rock solid but on closer examination (in light of the nature of the signatories across Protestant, Roman and Orthodox lines), there are some troubling aspects. I have highlighted the paragraph that concerns me and many others below:

We are Christians who have joined together across historic lines of ecclesial differences to affirm our right—and, more importantly, to embrace our obligation—to speak and act in defense of these truths. We pledge to each other, and to our fellow believers, that no power on earth, be it cultural or political, will intimidate us into silence or acquiescence. It is our duty to proclaim the Gospel of our Lord and Savior Jesus Christ in its fullness, both in season and out of season. May God help us not to fail in that duty.

So here is my problem. Are the issues that divide Protestants and Roman Catholicism (the institution, not so much individual Roman Catholics) merely “ecclesial differences”? Is it not the case that one of the wedges that drove these two groups apart was the very Gospel itself and that those varying understandings of the Gospel are mutually exclusive? I understand the goal here but my concern is that we are putting the priorities in the wrong order. I certainly agree that the primary duty of the believer is to proclaim the Gospel of Jesus Christ "in its fullness". Is that possible when the differences are so great?

There are certainly differences, regrettable and often sinful differences, between believers. Our prideful dogmatic stances that lead to separation on issues that are important (baptism) and far less important (the end times) have shattered the unity of the church and it is something we need to repent of. Having said that, I don’t see the differences between Presbyterian and Baptist brothers to be on par with differences between Protestants and Roman Catholicism. One is a difference in how we respond to the Gospel, the other is over the very nature of what the Gospel is.

Where am I going with this? In a nutshell, as critical as the three issues dealt with in the Manhattan Declaration are (abortion, gay marriage, religious freedom), I think we cross a dangerous line by linking arms with those who, in my opinion, have distorted the Gospel of grace into something…else. The Gospel, while simple, is not a place for us to seek the lowest common denominator and “enemy of my enemy is my friend” may work in warfare and politics but it has no place in the proclamation of the Gospel. I fear that in our zeal to see a common good we are forcing the Gospel into the backseat. No political victory or culture war struggle is more precious than the Gospel. We need to be careful about who we join with and call “brother”. It can be tempting to pool resources and provide a united front in doing social justice (adoption, fighting hunger, etc.) but we can lose the Gospel message in our zeal to do good works. There can be no justice outside of the Gospel proclamation. We must always put the first thing first.

(As an important side note, Albert Mohler who is one of the signers, addressed why he signed the Declaration. I am not sure I agree with his reasoning that this is not a theological document. What do you think?)