And to continue from my link:
Methods of Corruption
We learn about some of the types of changes made in the Christian texts because, ironically, they are clearly enumerated by the very people responsible for preserving them. For example Rufinus (fourth century) says of the earlier Christian texts he is copying: Wherever, therefore, we have found in his [in this case Origen’s] books anything contrary to that which was piously established by him about the Trinity in other places, either we have omitted it as corrupt and interpolated, or edited it according to that pattern that we often find asserted by himself. If, however, speaking to the trained and learned, he writes obscurely because he desires to briefly pass over something, we, to make the passage plainer, have added those things that we have read on the same subject openly in his other books….All who shall copy or read this…shall neither add anything to this writing, nor remove anything, nor insert anything, nor change anything.
In this Rufinus simultaneously and almost hypocritically pleads that others not do to him what he has done to them. Rufinus is explicitly following the example of his predecessors, specifically the example of Macarius “who when he translated over seventy works of Origen, which are called homilies and also several of his writings on the apostle into Latin in which are found several offensive passages, therefore he removed or cleaned up all of these when he translated, so that a Latin reader would find nothing in them that disagrees with our belief. This, therefore, we follow even if we are not so eloquent, nevertheless as much as we can, by the same rules, watching to be sure not to reveal those passages in the books of Origen that disagree and contradict with himself.” Deleting, altering, and even adding to works have been problems in antiquity, in the Renaissance, and even in the present day. But other types of corruptions also affect the text. One is the process by which the texts are reinterpreted in a non-literal or allegorical framework. Another is the changing of the meanings of words, such as occurred during the second sophistic period. Between the time of writing the New Testament and the end of the second century, the meanings of several of the words changed. Examples included the change of the principle meanings of pistis from “collateral, guarantee” to "belief, of homologein from “to agree to terms, accept an agreement, enter into a legal contract, promise” to “to confess;” of myst_rion from “(initation) rite” to “secret,” Because the New Testament is usually read with meanings of the second sophistic period and later-meanings which have often changed-the understanding of the text can be drastically changed… All of the methods of changing the text that we have just discussed occur in the second century.
Addition is also a textual corruption, though less frequent than deletion: Tertullian discusses entire forged “writings, which wrongly go under Paul’s name” and which circulated in his day.
Irenaeus accuses Valentinus of acting much like modern biblical critics and dividing "the prophecies [into different classes], maintaining that one portion was uttered by the mother, a second by her seed, and a third by the Demiurge.
“They gather their views from other sources than the Scriptures; and to use a common proverb, they strive to weave ropes of sand, while they endeavour to adapt with an air of probability to their own peculiar assertions the parables of the Lord, the sayings of the prophets, and the words of the apostles, in order that their scheme may not seem altogether without support. In doing so, however, they disregard the order and the connection of the Scriptures, and so far as in them lies, dismember and destroy the truth. By transferring passages, and dressing them up anew, and making one thing out of another, they succeed in deluding many through their wicked art in adapting the oracles of the Lord to their opinions.”
Motivations for Manipulating the Text
What motives did second century individuals and groups have to change scripture? Clement of Rome wrote his epistle at the beginning of the second century at the request of leaders in Corinth to settle a dispute they were having. Clement accuses individuals at Corinth of “pride and sedition” and as setting themselves up as “leaders” and usurping the authority that was not theirs. Toward the end of the second century, Clement of Alexandria notes that the Carpocratians changed scripture to sanction their own homosexual and other immoral practices. Irenaeus claims that the Tertullian says that “writings which wrongly go under Paul’s name” were forged by a presbyter in Asia to give “a license for women’s teaching and baptizing.” Changes in the texts and the motivations to alter the text of scriptures both canonical and non-canonical, in general, match those Nephi gave:
After the book hath gone forth through the hands of the great and abominable church, that there are many plain and precious things taken away from the book (1 Nephi 13:28).
Behold the gold, and the silver and the silks, and the scarlets, and the fine-twined linen, and the precious clothing, and the harlots, are the desires of this great and abominable church (1 Nephi 13:8).
While not all second century Christians were consumed by these desires, some clearly were.
fairlds.org/FAIR_Conferences/1999_Corruption_of_Scripture_in_the_Second_Century.html
In this case the great abominable church could be considered the people who were changing scripture to fit their needs and not the catholic church. And this is where Bruce R. McConkie made his mistake and of course, he was scolded for it. The abominable church are all those institutions and people which lead people from god.