The angel defines the nature of the great and abominable church as directly antithetical to Jehovah. Where Jehovah’s church produces saints of God, the abominable church tortures them. Jehovah’s church promises life to its believers. The abominable church slays them.
The great and abominable church is also defined as the opposite of Nephite egalitarian ideals. As king Mosiah will later teach, “there should be an equality among all men” (Mosiah 27:3). The vision shows the great and abominable church aspiring after gold, silver, and precious clothing, and harlots. It is not hard to see that that is the theme that Jacob, Nephi’s brother, preached against in his sermon before the temple. Nephi preached against the Nephite tendency to seek for wealth in gold and silver, to have many wives, and to wear costly apparel.
The great and abominable church is equated with the great and spacious building, and it is never far away from the Nephites, or indeed, any of us. It is the representation of the temptations that pull us away from the narrow path and the iron rod.
The beliefs and practices that characterize the great and abominable church were present among the Nephites at least as early as Jacob. That Nephi doesn’t see the formation of the church of the Devil until later does not mean that it didn’t exist prior, only that it becomes relevant to the final unrighteousness of all of Lehi’s seed and their destruction as nations only after the coming of the Gentiles from across the waters—the next part of the vision.