“Before commencing our examination of the evidence as to the date, authorship, and character of the Gospels, it may be well to make a few preliminary remarks, and clearly state certain canons of criticism.  We shall make no attempt to establish any theory as to the date at which any of the Gospels was actually written, but simply examine all the testimony which is extant, with the view of ascertaining what is known of these works and their authors, certainly and distinctly, as distinguished from what is merely conjectured or inferred ...  We propose, therefore, as exhaustively as possible, to search all the writings of the early Church for information regarding the Gospels, and to examine even the alleged indications of their use ...  It is still more important that we should constantly bear in mind that a great number of Gospels existed in the early Church which are no longer extant, and of most of which even the names are lost.  We need not here do more than refer, in corroboration of this fact, to the preliminary statement of the author of the third Gospel:  ’Forasmuch as many ([Greek:  polloi]) took in hand to set forth in order a declaration of the things which have been accomplish among us,’ &c.  It is, therefore, evident that before our third synoptic was written many similar works were already in circulation.  Looking at the close similarity of large portions of the three synoptics, it is almost certain that many of the writings here mentioned bore a close analogy to each other and to our Gospels, and this is known to have been the case, for instance, amongst the various forms of the ’Gospel according to the Hebrews.’  When, therefore, in early writings, we meet with quotations closely resembling, or, we may add, even identical, with passages which are found in our Gospels, the source of which, however, is not mentioned, nor is any author’s name indicated, the similarity or even identity cannot by any means be admitted as proof that the quotation is necessarily from our Gospels, and not from some other similar work now no longer extant, and more especially not when, in the same writings, there are other quotations from sources different from our Gospels....  But whilst similarity to our Gospels in passages quoted by early writers from unnamed sources cannot prove the use of our Gospels, variation from them would suggest or prove a different origin, and at least it is obvious that anonymous quotations which do not agree with our Gospels cannot in any case necessarily indicate their existence ...  It is unnecessary to add that, in proportion as we remove from Apostolic times without positive evidence of the existence and authenticity of our Gospels, so does the value of their testimony dwindle away.  Indeed, requiring, as we do, clear, direct and irrefragable evidence of the integrity, authenticity, and historical character of these Gospels, doubt or obscurity on these points must inevitably be fatal to them