Pilgrim
I am not a Presbyterian, however if the OPC and PCA is like many other denominations. Perhaps John is referring to their statement of faith?
Unfortunately, when my wife and I first came to live in the city we now live; we found several local Churches that had statements of faith that we could live with. However after attending those Churches for a few Sundays, we soon found out that their statements of faith meant very little to them.
Out of concern about this, in one case I interviewed their pastor, telling him my main concern. He proceeded to tell me in no uncertain terms, that what they teach and who they support is definitely in keeping with their statement of faith.
Needless to say, that was the last Sunday we attended there.

Tom