The concept of orthodoxy is not prominent in the thinking of mid-twentiethcentury writers on religion. There are many reasons for this. It is, for instance, always more interesting to challenge accepted traditions than to defend them, and publishers know that radical questioning generally attracts more attention than defence of received ideas. But the task of defending orthodox beliefs is an absolute necessity for the adherents of a revealed religion. It may be unpalatable to have to examine a long succession of ‘reinterpretations’ of Christianity, but it is important, since the new thinkers may often get things badly wrong, and the faithful (often woefully ill-armed–considering their individual capacity–for the intellectual fight) may be seduced by superficial plausibility or flashy modernity.One can well imagine a person who has found Christianity attractive enough for him to pray and to attend church services occasionally, but whose world-view has been largely formed by the mass media, discovering one of the modern ‘reinterpreters’ of the Christian faith with an enormous feeling of relief.