nÒIn the first of the books on the Gospel according to Matthew,
observing the ecclesiastical canon, he
testifies that he knows only four Gospels, writing
somewhat as follows: As he has learned by
tradition concerning the four Gospels, which alone
are undisputed in the Church of God under heaven,
that first there was written the Gospel
according to Matthew, the one-time publican but
afterwards an apostle of Jesus Christ, who published
it in the Hebrew language for those from
Judaism who believed.Ó
nComm on Matthew,
cited in Eusebius 6.25.3