I told the brethren that the Book of Mormon was the most correct of any book on earth, and the keystone of our religion, and a man would get nearer to God by abiding by its precepts, than by any other book. Joseph Smith, History of the Church, 4:461
It is the great and abominable church that was founded by the devil (to lead people to hell).
I beheld this great and abominable church; and I saw the devil that he was the founder of it. 1 Nephi 13:6
That great and abominable church, which was founded by the devil and his children, that he might lead away the souls of men down to hell. 1 Nephi 14:3
That great and abominable church, which is the mother of abominations, whose founder is the devil. 1 Nephi 14:9
God's wrath is upon it (the mother of harlots).
The wrath of God was poured out upon that great and abominable church.1 Nephi14:15
The wrath of God is poured out upon the mother of harlots, which is the great and abominable church of all the earth, whose founder is the devil.1 Nephi 14:17
It removed the plain and precious things from the Bible (to blind the eyes and harden the hearts of men).
A great and abominable church, which is most abominable above all other churches; for behold, they have taken away from the gospel of the Lamb many parts which are plain and most precious; and also many covenants of the Lord have they taken away. And all this have they done that they might pervert the right ways of the Lord, that they might blind the eyes and harden the hearts of the children of men.1 Nephi 13:26-27
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
The plain and most precious parts of the gospel of the Lamb which have been kept back by that abominable church.1 Nephi 13:32
Someday Catholics will kill each other and get drunk on their own blood.
And the blood of that great and abominable church, which is the whore of all the earth, shall turn upon their own heads; for they shall war among themselves, and the sword of their own hands shall fall upon their own heads, and they shall be drunken with their own blood.1 Nephi 22:13
And the Catholic Church (that great whore) will be destroyed.
That great whore, who hath perverted the right ways of the Lord, yea, that great and abominable church, shall tumble to the dust and great shall be the fall of it. 1 Nephi 22:14
Whoever doesn't fight against Zion (the LDS church) or become a Catholic will be saved.
They shall repent and fight not against Zion, and do not unite themselves to that great and abominable church, they shall be saved. 2 Nephi 6:12
The modern LDS church tries to deny that "the great and abominable church" in the Book of Mormon refers to the Roman Catholic Church. But here's what Bruce McConkey (a general authority) said about it in Mormon Doctrine:
It is also to the Book of Mormon to which we turn for the plainest description of the Catholic Church as the great and abominable church.