1. Pious Fraud

Dr. Herbert Marsh, 19th Century English Bishop:
It is a certain fact that several readings in our common printed text are nothing more than alterations made by Origen, whose authority was so great in the Christian Church (A.D. 230) that emendations which he proposed, though, as he himself acknowledged, they were supported by the evidence of no manuscript, were very generally received.2

Johann Lorenz Von Mosheim, 18th Century Ecclesiastical Historian:
Not long after Christ's ascension into heaven, several histories of his life and doctrines, full of pious frauds and fabulous wonders, were composed by persons whose intentions perhaps were not bad, but whose writings discovered the greatest superstition and ignorance. Nor was this all; productions appeared which were imposed upon the world by fraudulent men, [such] as the writings of the holy apostles.3

Johann Salomo Semler, 18th Century Theologian:
The Christian doctors never brought their sacred books before the common people; although people in general have been wont to think otherwise, during the first ages, they were in the hands of the clergy only.4

William Wake, 18th Century Archbishop of Canterbury:
It would be useless to insist on all the spurious pieces which were attributed to St. Paul alone, in the primitive ages of Christianity.5

Lucius Coelius Firmianes Lactantius, 3rd Century Advisor to the Roman Emperor Constantine:
Among those who seek power and gain from their religion, there will never be wanting an inclination to forge and lie for it.6

St. Gregory, 4th Century Bishop of Nazianzus, writing to St. Jerome:
A little jargon is all that is necessary to impose on the people. The less they comprehend, the more they admire. Our forefathers and doctors have often said not what they thought, but what circumstances and necessity dictated.7

Dr. Conyers Middleton, 18th Century Theologian:
There never was any period of time in all ecclesiastical history in which so many rank heresies were publicly professed nor in which so many spurious books were forged and published by the Christians, under the names of Christ, and the apostles, and the apostolic writers, as in those primitive ages. Several of these forged books are frequently cited, and applied [in] defense of Christianity, by the most eminent fathers of the same ages, as true and genuine pieces.8

Dr. I. Hooykaas, 19th Century Reverend:
Not one of these five books (four Gospels and Acts) [was] really written by the person whose name it bears, and they are all of more recent date than the heading would lead us to suppose.9

St. Faustus, 5th Century French Bishop:
Many things have been inserted by our ancestors in the speeches of our Lord which, though put forth under his name, agree not with his faith; especially since as already it has been often proved these things were written not by Christ, nor [by] his apostles, but a long while after their assumption, by I know not what sort of half Jews, not even agreeing with themselves, who made up their tale out of reports and opinions merely, and yet, fathering the whole upon the names of the apostles of the Lord or on those who were supposed to follow the apostles, they maliciously pretended that they had written their lies and conceits according to them.10

It is certain that the New Testament was not written by Christ himself, nor by his apostles, but a long while after them, by some unknown persons, who, lest they should not be credited when they wrote of affairs they were little acquainted with, affixed to their works the names of the apostles, or of such as were supposed to have been their companions, asserting that what they had written themselves were written according to these persons to whom they ascribed it.11

To strengthen belief in the resurrection of Jesus, St. Irenaeus invented many stories of others being raised from the dead.12 As Jeremiah Jones, an 18th Century Reverend, comments:
Such pious frauds were very common among Christians even in the first three centuries; and a forgery of this nature, with the view above mentioned, seems natural and probable.13

St. Augustine, 5th Century Bishop:
I was already Bishop of Hippo when I went into Ethiopia with some servants of Christ there to preach the Gospel. In this country, we saw many men and women without heads, who had two great eyes in their breasts; and in countries still more southly, we saw people who had but one eye in their foreheads.14

They saw nothing wrong with fooling the ignorant masses, reasoning that they were ultimately saving a populace steeped in unrighteousness, as the New Testament testifies:

I Peter 4:3

Let the time that is past suffice for doing what the Gentiles like to do, living in licentiousness, passions, drunkenness, revels, carousing, and lawless idolatry.