Washington’s iconic National Cathedral (an Episcopal church) announced this week that it will begin hosting same-sex “wedding” ceremonies. The announcement itself was not particularly surprising. The District of Columbia legalized civil marriages for same-sex couples in 2010, and the Episcopal Church has been moving away from Christian orthodoxy on the subject of homosexuality for even longer than that. In July of 2012, its General Convention authorized a set of “Liturgical Resources for Blessing Same-Sex Relationships.”

This development is being hailed in some quarters as being “symbolic” of an advance in the cause of redefining marriage. What it really symbolizes is the continued decline of the Episcopal Church in theUnited States, which is increasingly out of touch with the rest of worldwide Christianity, and with the rest of the worldwide Anglican communion.

The Episcopal Church is one of the fastest-shrinking denominations in the country, and their retreat from biblical ethics on the subject of homosexuality is a major part of the reason. The 2008 American Religious Identification Survey found that in just 7 years, from 2001 to 2008, the number of Americans identifying themselves as Episcopalian fell by over a million, from 3.5 million to only 2.4 million—a shocking decline of thirty percent. Not coincidentally, it was during this period that the church was rocked by the controversial 2003 decision to appoint the first openly homosexual Episcopal bishop, New Hampshire’s Gene Robinson.

The more Episcopal churches like the National Cathedral are filled with same-sex “weddings,” the less likely they are to be filled for worship on Sunday mornings.