And these portions of the Evangelic history, oral or partially documentary, would be adopted under the sanction of the Apostles, who were as in all things, so especially in this, the appointed and divinely-guided overseers of the whole Church. This _common substratum of Apostolic teachings_--never formally adopted by all, but subject to all the varieties of diction and arrangement, addition and omission, incident to transmission through many individual minds, and into many different localities--_I believe to have been the original source of the common part of our three Gospels_" ("Greek Test.," Dean Alford, vol. i., Prolegomena, ch. i., sec. 3, par. 6; ed. 1859. The italics are Dean Alford's). Eichhorn's theory of the growth of the Gospels is one very generally accepted; he considers that the present Gospels were not in common circulation before the end of the second century, and that before that time other Gospels were in common use, differing considerably from each other, but resting on a common foundation of historical fact; all these, he thinks, were versions of an "original Gospel," a kind of rough outline of Christ's life and discourses, put together without method or plan, and one of these would be the "Memoirs of the Apostles," of which Justin Martyr speaks. The Gospels, as we have them, are careful compilations made from these earlier histories, and we notice that, at the end of the second, and the beginning of the third, centuries, the leaders of the Church endeavour to establish the authority of the four more methodically arranged Gospels, so as to check the reception of other Gospels, which were relied upon by heretics in their controversies.