The following is an open letter from Oscar Beisert, an architectural historian and one of Philadelphia's most prominent preservationists, to the Faithful Laurentians, a group opposed to the planned redevelopment of Fishtown's St. Laurentius Roman Catholic Church into apartments.

Dear Faithful Laurentians:

Without knowing exactly who remains "faithful," I am left to appeal to your good nature in this public format. As you likely know, I have spent three years working to, as Philadelphia Magazine put it, "STOP" the demolition of historic properties in Philadelphia. In most cases, I stand with neighbors, concerned citizens, and fellow preservationists in the fight for Keeping Philadelphia. I now ask the same thing of well-meaning neighbors and fellow preservationists who I fear are allowing the perfect to stand in the way of the good in their impractical and untimely quest to preserve a sacred interior space.

Being a native Texan, I am not technically "at home" in Philadelphia, yet somehow, there is no place in America that speaks more genuinely to my heart and soul and, by my mind, to the overall spirit and story of our national heritage. Nearly everywhere I look in the Quaker City, I see amazing and irreplaceable vestiges of an old world that makes Philadelphia a most special place. While I am not alone in my feelings for the city, there are many more who don't clearly see what is before their eyes and seek to "improve" by way of destruction our remarkable and unique built heritage. With only 2.2 percent of the city's buildings protected from a developer's wrecking ball, the pressure of development and the threat of loss is looming at nearly every old corner. So many of the vestiges that I know to be remarkable, quaint, or special stand in harm's way. And of all the developers and capitalists that operate in this city, only a fraction see what I see in our embarrassment of riches.

Among these treasures is the incredible and monumental edifice known as St. Laurentius Roman Catholic Church. The Fishtown landmark appears just as tall and proud as it does staunch and permanent. Yet, in all of its outward mightiness, this built legacy of Philadelphia's Polish Catholics cannot stand on its own without a caretaker. The major problem with this landmark is fairly simple: The building is, in all its glory, bathed in a beautiful but toxic brownstone, a chocolate sauce that is prone to failure, making it among the most vulnerable of stone types. If this building was nothing more than its architecture, we could possibly wash our hands and lament its passing, but it means so much more in the context of working-class Philadelphia. Unfortunately, the building's history possesses a type of value that doesn't easily or immediately equate to the many hundreds of thousands of dollars it will cost to ensure its permanence.

More than three years ago, I volunteered my time on behalf of Save St. Laurentius, a group of neighbors and former parishioners who sought to preserve the church, to successfully designate this important building before the Philadelphia Historical Commission.

However, I knew then, as I know now, that historic designation can only temporarily save a building. It is like an insurance policy of sorts, giving interested citizens a nexus to fight for preservation. I knew that ultimately it would take one of those rare developers, perhaps a less-capitalistic one, to make this building self-sufficient in the modern world. If it were constructed of brick or schist, maybe even wood, the circumstances might be different, but brownstone is perhaps the most expensive stone to maintain and even more so to repair.

Against all of the odds, after painstaking efforts, Save St. Laurentius found a new caretaker — a developer that remains committed to making this landmark economically self-sufficient. The plan is to preserve the exterior and some original interior details of the building.

It is a better deal for preservation and public good than it is for the pockets of its developer. Interestingly, the plan adheres to an age-old tradition of reuse in Philadelphia that harkens to the spirit of our Quaker founders, which is why so many "ancient" buildings survive today. But how much longer will this community-minded developer be willing to wait around? And even if the developer is willing to wait, can the building survive that wait? What if this unprecedented hurricane season produces a bad storm that passes through Philadelphia? Or winter brings just one really bad snowstorm? In any of these circumstances, and even if no further damage occurs, the archdiocese, which still owns St. Laurentius, has the perfect case to win a financial hardship ruling in their favor, allowing for the church's complete demolition.

And when the walls of this icon come down, and come down they will if they aren't adaptively reused, it will not be the fault of the archdiocese or the indefatigable greed of developers. It will be the consequence of well-meaning neighbors, citizens and preservationists who were unwilling to compromise.

With the greatest respect for the motives of the Faithful Laurentians, I ask of you what I once successfully required of the archdiocese (only to you I will say please): STOP!

Save St. Laurentius. Save Philadelphia.

This piece was first published on PlanPhilly.com, a project at WHYY.