There is much dialog in the PCUSA about recent changes made to the Book of Order. For those troubled by the recent removal of the "fidelity and chasity" clause from the Constitution, essentially leaving the denomination silent on ordination of sexually active homosexuals, I think Alan Wisdom of the Institute on Religion and Democray has some good insights in his article Stay or Go?:
"... I do not see a single clear scriptural answer to how we should relate to a 21st century Protestant denomination that has ceased to uphold the biblical teaching on sexuality. There are some passages that seem to counsel separation from those who turn the Gospel into a license for sin (e.g., Ephesians 5:3-7). On the other hand, we have the example of the Apostle Paul, who never gave up on the Corinthian church even though it was plagued by all kinds of errant beliefs and behaviors. It is not so easy to take New Testament passages about the universal Church, the whole Body of Christ, and apply them directly to a modern invention—the Presbyterian Church (U.S.A.), established 1983—that has never been more than a sliver of the whole.
There are good reasons to remain in the PCUSA, and good reasons to leave. Those of us who are ministers, elders, or deacons freely took vows to be “governed by our church’s polity and … abide by its discipline.” When we took those vows, most of us knew that the PCUSA had serious problems. Can we now set those vows aside because the problems have grown worse?
The deletion of the “fidelity and chastity” standard from the Book of Order does not, so far, compel any of us to violate our conscience. If we believe that standard reflects the teaching of Scripture—a higher authority than the Book of Order—then we can and must continue to hold ourselves accountable to it. Nothing stops us from obeying it in our churches and presbyteries. Nothing forces us to call a minister or elect an elder involved in a non-marital sexual relationship. That situation may change in the future, as revisionists demand as a matter of “justice” that prospective ministers be willing to ordain and marry those in same-sex relationships. But we have not yet reached that pass.
In the meantime, the PCUSA provides a wide space for faithful believers to proclaim and live out the Gospel. ..."