Moving on from Roman Catholic and Eastern Orthodoxy theologies as examples of theologies in which supporters strongly believe they adhere to a consistent theological system, a question arises about non-Anglican, non-Roman, non-Eastern theologies (i.e. Protestant theologies anchored in the Continental Reformation). I realise that I do not know enough about Calvinism and Lutheranism to say much about their consistency or otherwise. I guess their shared weak point is getting the relationship between Scripture (which figures very large in all Protestant theologies) and non-Scripture right. By 'non-Scripture' I mean the mixture of tradition (here, in a Protestant context, how the church has interpreted Scripture through the ages) and discernment (how the church determines in its present context either what the meaning of Scripture is, or what the Spirit is saying to the church on a matter on which Scripture says nothing). This is a weak point because, depending how the relationship between Scripture and non-Scripture is worked out, it may incur the charge of "pick 'n' mix" (e.g. why choose the decisions of these ecumenical councils and not the decisions of those ones?) or "bias" (e.g. why weight teaching on salvation towards Romans and Galatians rather than towards Matthew 5 and James?), to say nothing of the charge of offering an inadequate account of "authority" (e.g. who appointed Calvin to be God's spokesperson, or why does the congregation (i.e. smallest unit of the church) have so much say in discernment of God's will?)
A further point may be made about Protestant theologies: as they are worked out, they tend to involve a large amount of continuation of the theology of the universal church (e.g. holding to rather than revising the ancient creeds, retaining Scripture (albeit with variation in importance of the Apocrypha), as well as strong emphasis on the points of protest against medieval Roman Catholic theological understandings (some of which have been reworked by Roman Catholic theologians). Why maintain a theological apparatus from a separate standpoint when so much is in common with the theological apparatus based in Rome?
Time does not permit me to continue this line of thinking, but any Protestants reading here who wish to comment are most welcome. Tomorrow I aim to move from this set of observations to think about Anglican theologies and their consistency, or otherwise.