hese two,
according to the law of Biogenesis, are separated from one another by
the deepest line known to Science. This Law is at once the foundation of
Biology and of Spiritual religion. And the whole fabric of Christianity
falls into confusion if we attempt to ignore it. The Law of Biogenesis,
in fact, is to be regarded as the equivalent in biology of the First Law
of motion in physics: _Every body continues in its state of rest or of
uniform motion in a straight line, except in so far as it is compelled
by force to change that state._ The first Law of biology is: That which
is Mineral is Mineral; that which is Flesh is Flesh; that which is
Spirit is Spirit. The mineral remains in the inorganic world until it
is seized upon by a something called Life outside the inorganic world;
the natural man remains the natural man, until a Spiritual Life from
without the natural life seizes upon him, regenerates him, changes him
into a spiritual man. The peril of the illustration from the law of
motion will not be felt at least by those who appreciate the distinction
between Physics and biology, between Energy and Life. The change of
state here is not as in physics a mere change of direction, the
affections directed to a new object, the will into a new channel. The
change involves all this, but is something deeper. It is a change of
nature, a regeneration, a passing from death into life. Hence relatively
to this higher life the natural life is no longer Life, but Death, and
the natural man from the standpoint of Christianity is dead. Whatever
assent the mind may give to this proposition, however much it has been
overlooked in the past, however it compares with casual observation, it
is certain that the Founder of the Christian religion intended this to
be the keystone of Christianity. In the proposition _That which is flesh
is flesh, and that which is spirit is spirit_, Christ formulates the
first law of biological religion, and lays the basis for a final
classification. He divides men into two classes, the living and the
not-living. And Paul afterward carries out the classification
consistently, making his entire system depend on it, and throughout
arranging men, on the one hand as {pneumatikos}--spiritual, on the other
as {psychikos}--carnal, in terms of Christ's distinction.

Suppose now it be granted for a moment that the character of the
not-a-Christian is as beautiful as that of the Christian. This is simply
to say that the