and the collective consciousness.  We have already touched on this aspect of the impossibility of obtaining sufficient strength for the warfare of the present in anything that occurred in the past.  Some measure of strength—­and no psychology is able to say how much—­can be obtained from a vision of the spiritual meaning and significance of the life of the Founder.  But there is very great danger in looking here alone for the sole source of all the help we need.  The spiritual principles of Christianity have been operating in the world ever since the Master presented the Gospel which he lived and died for.  The problem of Christianity is thus a twofold problem.  On the one hand, we have constantly to go back to the Fountain-head, because it is here that the stream is purest.  But we have, on the other hand, to enter into the religious current which surrounds us; and this may be not so [p.183] pure as it was at its source.  Alien waters have entered into the current—­waters of very different taste from those which even the Founder expected.  These have doubtless polluted the stream.  But, on the other hand, good elements—­primary and secondary—­have entered into the deepest nature of Christianity itself.  These have to be taken into account.  They have been necessitated by the new and ever more complex situations and conditions into which Christianity has had to enter from generation to generation.  It was comparatively easy for Christianity in its early beginnings to include within its compass the whole of life.  But by to-day life has branched off in so many new directions; perplexing problems of knowledge and life have made their appearance.  We dare not dismiss these to a region outside the sphere of influence of Christianity.  Christianity, if it is to remain and increase as a living force, has to interpret these problems; it has to help us to distinguish between the chaff and the wheat.

What, then, is the true meaning of Christianity?  Eucken shows that it is not possible to determine the nature of Christianity without realising that the nucleus common to all religions lies in the fact “that they manifest and represent a Divine Life, and that such a Life in its inmost foundation is superior to its external configuration and activity, and is able to withstand all the changes of time, and to [p.184] maintain within itself, in spite of all its curtailment through the human situation, an eternal truth.”  This nucleus lies deeper in Christianity than in any other religion.  But even Christianity itself is not a pure spiritual nucleus.  Much, as we have already noticed, has gathered around it—­much that reveals a lower grade of spirituality.  All this constitutes the clothing of Christianity.  The clothing has been changed again and again in the past.  What reason is there for affirming that it cannot be changed again?  It is therefore necessary to differentiate between the Substance of Christianity and its Existential-form.  The Substance