Firstly, as to Luke, doubt is scarcely possible.  The Gospel of Luke is a regular composition, founded on anterior documents.[1] It is the work of a man who selects, prunes, and combines.  The author of this Gospel is certainly the same as that of the Acts of the Apostles.[2] Now, the author of the Acts is a companion of St. Paul,[3] a title which applies to Luke exactly.[4] I know that more than one objection may be raised against this reasoning; but one thing, at least, is beyond doubt, namely, that the author of the third Gospel and of the Acts was a man of the second apostolic generation, and that is sufficient for our object.  The date of this Gospel can moreover be determined with much precision by considerations drawn from the book itself.  The twenty-first chapter of Luke, inseparable from the rest of the work, was certainly written after the siege of Jerusalem, and but a short time after.[5] We are here, then, upon solid ground; for we are concerned with a work written entirely by the same hand, and of the most perfect unity.

[Footnote 1:  Luke i. 1-4.]

[Footnote 2:  Acts i. 1.  Compare Luke i. 1-4.]

[Footnote 3:  From xvi. 10, the author represents himself as eye-witness.]

[Footnote 4:  2 Tim. iv. 11; Philemon 24; Col. iv. 14.  The name of Lucas (contraction of Lucanus) being very rare, we need not fear one of those homonyms which cause so many perplexities in questions of criticism relative to the New Testament.]

[Footnote 5:  Verses 9, 20, 24, 28, 32.  Comp. xxii. 36.]

The Gospels of Matthew and Mark have not nearly the same stamp of individuality.  They are impersonal compositions, in which the author totally disappears.  A proper name written at the head of works of this kind does not amount to much.  But if the Gospel of Luke is dated, those of Matthew and Mark are dated also; for it is certain that the third Gospel is posterior to the first two and exhibits the character of a much more advanced compilation.  We have, besides, on this point, an excellent testimony from a writer of the first half of the second century—­namely, Papias, bishop of Hierapolis, a grave man, a man of traditions, who was all his life seeking to collect whatever could be known of the person of Jesus.[1] After having declared that on such matters he preferred oral tradition to books, Papias mentions two writings on the acts and words of Christ:  First, a writing of Mark, the interpreter of the apostle Peter, written briefly, incomplete, and not arranged in chronological order, including narratives and discourses, ([Greek:  lechthenta e prachthenta],) composed from the information and recollections of the apostle Peter; second, a collection of sentences ([Greek:  logia]) written in Hebrew[2] by Matthew, “and which each one has translated as he could.”  It is certain that these two descriptions answer pretty well to the general physiognomy of the two books now called “Gospel