Reading around the internet, noting, for instance, criticisms of Anglicans and their beliefs, perhaps from a recent Anglican who has now formally subscribed to Roman doctrine, I note that criticism of Anglican theologies re internal consistency occurs in broadly two ways. One is Anglican v Anglican along the "How can you as (say) an evangelical Anglican subscribe to X and not also to Y?" Explicitly or implicitly the associated jibe is "By contrast the liberal/catholic/other Anglicanism to which I subscribe escapes such charges; perhaps you ought to take it more seriously!" The other criticism is a "plague on all your houses" critique: "It doesn't matter what variety of Anglicanism tries to be serious about theology, it is intrinsically flawed because it lacks X, Y, or Z," with the flaws noted likely to relate to the question of 'authority'.
Of course critics from outside Anglicanism have something of an easy time finding something to criticise: we are all over the shop. Bryan Owen, in the post I noted yesterday, cites from a writer Carston T. Clark a lovely paragraph expressing our mind-boggling diversity! Those external critics - as I understand it - believe their vantage point to be one of consistency in theology.
Thus Roman Catholic theology holds itself to be consistent because nothing lies within it which has not been approved by proper authority, i.e. the Pope, and its own belief concerning this authority is that it is divine authority because the Pope is 'the Vicar of Christ'. I summarise, of course, a complex theological argument about the ongoing role of the Holy Spirit in the life of the church, the role of councils of bishops, and the reasons why Rome's bishop and not another is the apex of the Roman understanding of ecclesial authority. The achilles heal of the Roman system of belief lies precisely at the point of its proclaimed strength: what if the Pope is not the Vicar of Christ (e.g. because Christ did not found such a role)? Nevertheless, accept the papal claims and there is good consistency, not least because any change in doctrine (or practice), even a reversal, would always be approved by the pope and thus always consistent as a 'papally approved' teaching.
Eastern Orthodox theology holds itself to be consistent because nothing within it lies outside what has been approved by the first seven Ecumenical Councils. In one sense (providing any tensions within the set of decisions made by those councils is able to be lived with) there is no possibility of theological inconsistency because such a possibility never occurs. Theoretically it could occur, when an Eighth Ecumenical Council took place, but in practice this is not going to happen this side of the Second Coming. Whereas a strength of Roman theologising is the possibility of development being accommodated in the growing body of papally approved doctrine, a weakness of Eastern Orthodox theology is it has no mechanism for making reasonable adaptation of its theology in the light of real gains in knowledge, insight, or experience of life. (Or does it?). Acknowledged here is an attractive strength and security for Western Christians converting to Eastern Orthodoxy: the stresses and strains of theological reform and development will never again be encountered. (But a caveat emptor would be a warning about power crazed patriarchs providing a different source of stress!)
Have got to stop there for today, but I will be thinking about 'consistent' non-Anglican-but-Protestant theologies.