Because, if the events related in the life of Christ have been previously related as parts of the lives of earlier mythical gods, we find ourselves confronted by the possibilities that what is mythical in one narrative may be mythical in another; that if one god is a myth another god may be a myth; that if 400,000,000 of Buddhists have been deluded, 200,000,000 of Christians may be deluded; that if the events of Christ's life were alleged to have happened before to another person, they may have been adopted from the older story, and made features of the new.
If Christ was God—the omnipotent, eternal, and only God—come on earth, He would not be likely to repeat acts, to re-act the adventures of earlier and spurious gods; nor would His divine teachings be mere shreds and patches made up of quotations, paraphrases, and repetitions of earlier teachings, uttered by mere mortals, or mere myths.
What are we to think, then when we find that there are hardly any events in the life of Christ which were not, before His birth, attributed to mythical gods; that there are hardly any acts of Christ's which may not be paralleled by acts attributed to mythical gods before His advent; that there are hardly any important thoughts attributed to Christ which had not been uttered by other men, or by mythical gods, in earlier times? What are we to think if the facts be thus?
Mr. Parsons, in Our Sun God, quotes the following passage from a Latin work by St. Augustine:
Again, in that I said, "This is in our time the Christian
religion, which to know and also follow is most sure and
certain salvation," it is affirmed in regard to this name,
not in regard to the sacred thing itself to which the name
belongs. For the sacred thing which is now called the
Christian religion existed in ancient times, nor, indeed,
was it absent from the beginning of the human race until
the Christ Himself came in the flesh, whence the true religion
which already existed came to be called "the Christian." So
when, after His resurrection and ascension to heaven, the
Apostles began to preach and many believed, it is thus written,
"The followers were first called Christians at Antioch."
Therefore I said, "This is in our time the Christian religion,"
not because it did not exist in earlier times, but as having
in later times received this particular name.
From Eusebius, the great Christian historian, Mr. Parsons, quotes as follows:
What is called the Christian religion is neither new nor
strange, but—if it be lawful to testify as to the truth—
was known to the ancients.
Mr. Arthur Lillie, in Buddha and Buddhism, quotes M. Burnouf as saying:
History and comparative mythology are teaching every day
more plainly that creeds grow slowly up. None came into the
world ready-made, and as if by magic. The origin of events
is lost in the infinite. A great Indian poet has said: "The
beginning of things evades us; their end evades us also; we
see only the middle."
Before Darwin's day it was considered absurd and impious to talk of "pre-Adamite man," and it will still, by many, be held absurd and impious to talk of "Christianity before Christ."