There is another side: the quid pro quo of entryism. It is that the institution has a right to determine its boundaries and to police them.
Half the problem in some Churches is that no one is sure where the boundaries are set. There are forms of words but they have long been circumvented. I've listened to people give the Declaration of Assent not long after having a chat with them when they have, in discussion, denied elements of something they declare. They declare the creeds and historic formularies - so the latter is just the thrust of the Thirty-nine Articles
Soon the Church of Ireland will see the Archbishop of Dublin and Bishop of Down & Dromore table motions about human sexuality to its General Synod. It might be possible to kick these into the long grass. Some opponents say that there has been a lack of time for consideration. One resolution says sexual expression only within heterosexual marriage and the other is a sort of 'behave yourself when you talk about gays' as if this latter resolution makes the first non-homophobic. Of course the position is homophobic: it is generated in a dislike for what gays do, and translates into institutional inequality and exclusion. It is framed in terms of scripture and tradition as if this gives the exclusion moral force, when all it does is show the inappropriate use of scripture as it has nothing to say about sexuality as such.
But if the resolutions are passed then the Church has made a decision, and the only honourable course then is for gay people and sympathisers to leave. The Church does not presume a membership nor does anyone owe it their membership. If you don't like the boundaries, go and start a Church without them. Of course there can be campaigning against the boundaries, but these will be freshly laid.
The situation in the Church of England is slightly different in that there is more flux to the situation. Many of us campaigned against the Covenant and that has gone, and there should be female bishops in prospect. The closet gays are the ones most likely to leave, or disappear into a traditionalist Anglo-Catholic closet altogether until death or retirement. It is a tradition passing to a Roman Catholic ordinariate.The boundaries are thus in contention, under pressure, and the final outcome is still open. With the Covenant gone, the way is potentially open towards gay inclusion, though I doubt it will happen. But if the C of E was to resolve to exclude gay people in loving relationships from blessings and ministry then they should leave.
I'm in a Church that has no exclusions regarding gay people in ministry, and is campaigning for equality of marriage. Civil Partnerships in religious premises (the partnership itself still has to be secular) is hardly equality, even if it represents progress in recent times. On the other hand, my Church has doctrinal freedoms that many gay Christians would not want. But the answer is that once a Church determines its boundaries it has a right to enforce them. Now the Church of England claims a duty regarding everyone and all places, but it is quite normal to dissent from this and put oneself outside.
It will have to enforce them if entryists get busy, otherwise the entryists will burrow away and succeed. The host will be altered according to the efforts of the entryist. By all means campaign but if a recent decision gets made that excludes, then it is best to obey it and get out. The Covenant would have been such a decision for liberals to consider their position (in my opinion.
A view from the gallery - http://changingattitude.org.uk/wp-content/uploads/2017/02/GS-A-View-From-the-Gallery-75x42.jpg 75w" sizes="(max-width: 299px) 100vw, 299px" /> When I was a ...