Nearly 180 years ago David Friedrich Strauss analyzed what he called the rationalistic doctrine of historical Jesus studies. It is here where the biblical scholar peels back the layer upon layer of myth and legend associated with the Jesus story in order to arrive at the true kernel of some past individual from which the entire Christian religion evolved.
But Strauss noticed a problem with this method. Namely, could the spread of Christianity really be explained as emanating from this entirely mundane, historically invisible person? Once one whittles away the mythical and legendary elements of the story, little is left for evaluating the historical Jesus. This is one reason scholars constantly produce any number of Jesuses: revolutionary, messiah, cynic, wise sage, rabble rouser, socialist, conservative, Buddhist, the list goes on.
Jesus becomes whomever the interpreter wants. But in accepting this unimportant, vague, undefinable historical Jesus as the “true” Jesus, we quickly undermine fundamental Christian orthodoxy. The mythical and legendary stories found in the gospels are precisely the elements of Jesus which make him a special character of history according to Christians. Without Christology there is no Christianity.
In his critique of the rationalistic view of biblical history, Strauss sums up the problem nicely:
If Christ was no more, and did no more, than this rationalistic doctrine supposes, it is not easy to see how piety has come to make him her special object, or dogmatism to lay down special propositions concerning him. Consistent Rationalists have in fact admitted, that what the orthodox dogma calls Christology, forms no integral part of the rationalistic system, since this system consists indeed of a religion which Christ taught, but not of a religion of which he is the object; that, viewing Christology as the doctrine of the Messiah, it is merely an accommodation to the Jewish mind,—that even taken in a more noble sense, as the doctrine of the life, the actions, and the fate of Jesus as a divine messenger, it does not belong to a system of faith, for the universal truths of religion are as little connected with our ideas concerning the person of him who first enunciated them, as are the philosophical propositions in the systems of Leibnitz and Wolf, of Kant, Fichte, and Schelling, with the opinions we may happen to form of the persons of their authors; that what relates to the person and work of Jesus belongs, not to religion itself, but to the history of religion, and must either be prefixed to a system of religious doctrine as an historical introduction, or appended to it as an elucidatory sequel.
Thus, however, Rationalism enters into open war with the Christian faith, for it seeks to thrust into the background, nay, to banish from the province of theology, that which is its essential point, and corner-stone. But this very opposition is decisive of the insufficiency of the rationalistic system, proving that it does not perform what is demanded from every system of religious doctrine: namely, first, to give adequate expression to the faith which is the object of the doctrine; and secondly, to place this expression in a relation, whether positive or negative, to science. Now the Rationalists, in the effort to bring the faith into harmony with science, restrict its expression; for a Christ who is only a distinguished man creates indeed no difficulty to the understanding, but is not the Christ in whom the Church believes.