In the letter, dated Wednesday, ACNA Archbishop the Most Rev. Robert Duncan compared the two bodies to two cities – one of which is the City of God and the other of which is the City of the World.
"Both cities are in crisis, but one operates from received values and behaviors, while the other attempts to re-make the world to its own revolutionary tastes," he wrote.
Duncan, obviously, referred to the ACNA – comprised of conservative Anglicans in the United States and Canada who broke from The Episcopal Church and the Anglican Church of Canada – as the body of believers who "embraced the values and behaviors familiar to Christians in every age" during their inaugural assembly last month in Bedford, Texas.
The Episcopal Church, meanwhile, "blessed the values and behaviors of a re-defined Christianity," including "confusing received understandings of Scriptural truth" and "enabling a revisionist anthropology," during its General Convention in Anaheim, Calif., this month, Duncan noted.
"There are times in the history of God's people when the prevailing values and behaviors of those then in control of rival cities symbolizes a choice to be made by all of God's people. For Anglicans such a moment has certainly arrived," he wrote. "The cities symbolizing the present choice are Bedford, Texas, and Anaheim, California."
Last week, Episcopal leaders approved resolutions that open the denomination's ordination process to all individuals, including practicing homosexuals, and also call for the development of theological and liturgical resources around the blessing of same-sex unions.
Although the Episcopal presiding bishop, Katharine Jefferts Schori, said they are still committed to the wider Anglican Communion – which had urged U.S. Episcopalians not to pass any gay-affirming legislation – and clarified that the resolutions did not rescind an earlier ban on gay ordination and does not authorize public rites for the blessing of same-sex unions, orthodox Anglicans say The Episcopal Church has gone too far.
Earlier, Anglicans disaffected by what they argue is The Episcopal Church's departure from Scripture and traditional Anglicanism established their own conservative province in an attempt to distance themselves from the U.S. body and stay aligned with the global Anglican Communion. The ACNA is seen as a rival body to The Episcopal Church and the Anglican Church of Canada.
"For Anglican Christians, for the Instruments of Unity (Communion), for interdependent Provinces, for ordinary believers, there is a choice to be made," Duncan stated in his letter. "The choice is between two religions, two roads, two cities, two sets of conflicting values and behaviors. In Deuteronomy, chapter 30, Moses sets the choice as between blessing and curse, life and death. For contemporary Anglicanism the present choice is this stark."
The Rev. Mark Harris, an Episcopal priest in the Diocese of Delaware, interpreted the letter as saying the ACNA is an instrument of life and a blessing while The Episcopal Church is an instrument of death and a curse.
Harris says Duncan's letter makes it impossible to consider a worldwide Anglican Communion in which both The Episcopal Church and the ACNA exist together and are both recognized as provinces in North America.
It is unprecedented to establish an Anglican national province where such a national church already exists. The ACNA has not received formal recognition from the Archbishop of Canterbury, the spiritual leader of the global communion, but nine of the communion's 38 provinces indicated support for the ACNA.