statements of religion which men of a former generation may have found
serviceable. The distinction between religion itself, on the one hand,
and the expression of religion in doctrines and rites, or the
application of religion through institutions, on the other hand, is in
itself one of the great achievements of the nineteenth century. It is
one which separates us from Christian men in previous centuries as
markedly as it does any other. It is a simple implication of the Kantian
theory of knowledge. The evidence for its validity has come through the
application of historical criticism to all the creeds. Mystics of all
ages have seen the truth from far. The fact that we may assume the
prevalence of this distinction among Christian men, and lay it at the
base of the discussion we propose, is assuredly one of the gains which
the nineteenth century has to record.

It follows that not all of the thinkers with whom we have to deal will
have been, in their own time, of the number of avowedly Christian men.
Some who have greatly furthered movements which in the end proved
fruitful for Christian thought, have been men who in their own time
alienated from professed and official religion. In the retrospect we
must often feel that their opposition to that which they took to be
religion was justifiable. Yet their identification of that with religion
itself, and their frank declaration of what they called their own
irreligion, was often a mistake. It was a mistake to which both they and
their opponents in due proportion contributed. A still larger class of
those with whom we have to do have indeed asserted for themselves a
personal adherence to Christianity. But their identification with
Christianity, or with a particular Christian Church, has been often
bitterly denied by those who bore official responsibility in the Church.
The heresy of one generation is the orthodoxy of the next. There is
something perverse in Gottfried Arnold's maxim, that the true Church, in