The PCUSA’s Decision to Ordain Practicing Homosexuals

I just read that the PCUSA (the denomination to which I belong) has made the decision to begin ordaining practicing homosexual ministers:

http://www.christianpost.com/news/pcusa-votes-to-allow-openly-gay-clergy-50176/

I'm still struggling with how to respond to this. My concern is not precisely with the details of this decision, but with the reasoning behind it.  The theological shifts necessary to make this seem reasonable require that we ignore the unanimous witness of Scripture, two thousand years of Christian reflection and praxis, and the all-but-unanimous consensus of Christians around the world. The PCUSA has apparently decided that these are no longer authoritative, and that strikes me as a very dangerous step. If we're no longer to be constrained by any of these three sources of authority, the PCUSA will almost certainly find itself “blown about by every wind of doctrine.” Fashion, not faithfulness, will reign. In another hundred years, without any solid authority as a guide, it will only be by the grace of God if the PCUSA remains a recognizably Christian organization.

The possibility of apostasy may seem remote now, but when you consider how John Calvin or John Knox would view this move, I think you can get a sense for how far the PCUSA has already shifted from its foundations. Yet this is not just an abandonment of its own roots in the Reformation: it's a clear step away from its ties to historic Christian faith and practice, and to the larger Christian communion worldwide. That more than anything else is what frightens me.

I'm no fundamentalist, but this is a bright line for me and for my wife. We love our church, but our primary commitment is to Christ, to His Word, and to the great traditions of His Body, and we need to be a part of a denomination with the same goals.