nual called the _Didache_, or _Teaching of
the Twelve Apostles_, in ch. xv.: "Reprove one {10} another, not in
anger but in peace, as ye have it in the gospel." This book was
probably composed about A.D. 100. The word seems to have been still
more definitely applied to a written account of the life of Christ in
the time of the great heretic Marcion, A.D. 140. The plural word
_euaggelia_, signifying the Four Gospels, is first found in a writing
of Justin Martyr,[1] about A.D. 152. It is important to notice that he
also calls them "Memoirs of the Apostles," and that he refers to them
collectively as "the Gospel," inasmuch as they were, in reference to
their distinctive value as records of Christ, one book.

[Sidenote: Their Genuineness.]

The first three Gospels do not contain the name of the writers in any
connection which can be used to prove conclusively that they were
written by the men whose names they bear. On the other hand, the
fourth Gospel in a concluding passage (John xxi. 24) contains an
obvious claim to have been written by that intimate friend of Jesus to
whom the Church has always attributed it. But the titles, "according
to Matthew," "according to Mark," "according to Luke," rest on
excellent authority. And they imply that each book contains the good
news brought by Christ and recorded in the teaching of the evangelist
specified. These titles must, _at the very least_, signify that the
Christians who first gave these titles to these books, meant that each
Gospel was connected with one particular person who lived in the
apostolic age, and that it contained nothing contrary to what that
person taught. The titles, taken by themselves, are therefore
compatible with the theory that the first three Gospels were perhaps
written by friends or disciples of the men whose names they bear. But
we shall afterwards see that there is overwhelming evidence to show
that the connection between each book and the specified person is much
closer than that theory would suggest.

Speaking of the four Gospels generally, we may first observe that it is
impossible to place any one of them as late as A.D. 100, {11} and that
the first three Gospels must have been written long before that date.
This is shown by the internal evidence, of which proof will be given in
detail in the chapters dealing with the separate Gospels. The external
evidence of the use of all the four Gospels by Christians, and to some
extent by non-Ch