8 But the harmony between them we will establish, both by the whole world, which has received their statements, and by the very enemies of the truth. For many sects have had birth, since their time, holding opinions opposed to their words; whereof some have received all that they have said, while some have cut off from the rest certain portions of their statements, and so retain them for themselves. But if there were any hostility in their statements, neither would the sects, who maintain the contrary part, have received all, but only so much as seemed to harmonize with themselves; nor would those, which have parted off a portion, be utterly refuted by that portion; so that the very fragments cannot be hid, but declare aloud their connection with the whole body. And like as if you should take any part from the side of an animal, even in that part you would find all the things out of which the whole is composed—nerves and veins, bones, arteries, and blood, and a sample, as one might say, of the whole lump—so likewise with regard to the Scriptures; in each portion of what is there stated, one may see the connection with the whole clearly appearing. Whereas, if they were in discord, neither could this have been pointed out, and the doctrine itself had long since been brought to nought: “for every kingdom,” says He, “divided against itself shall not stand.” But now even in this shines forth the might of the Spirit, namely, in that it prevailed on these men, engaged as they were in those things which are more necessary and very urgent, to take no hurt at all from these little matters.
Now, where each one was abiding, when he wrote, it is not right for us to affirm very positively.
But that they are not opposed to each other, this we will endeavor to prove, throughout the whole work. And thou, in accusing them of disagreement, art doing just the same as if you were to insist upon their using the same words and forms of speech.
Source: Homilies on the Gospel of St. Matthew (New Advent)