There are many clear messages in the Book of Mormon, and one of them is that those who serve God will prosper in the land, and those who do not will be cut off from his presence. This is repeated so often in the text any sane modern publisher would beg the author/editor to remove at least half of them.
However, if one were about to be barreled over by a locomotive you would desire the loudest, clearest, most unambiguous warning possible to move out of the way.
The Book of Mormon contains the account of the destruction of three nations. The Nephite nation is born from the destruction of the Jews. The book concludes with the Nephite destruction, while the Lamanites descend into primal ferocity and their own form of destruction. Moroni abridges the account of the Jaredites and their destruction. The Jews, Nephites, and Jaredites – three once previously select nations destroyed by the wrath of God. The message could not be clearer for those who receive the record.
In case the message is still somehow missed in the narrative, Moroni writes the following to the reader in an editorial note as he relates the history of the Jaredites:
Ether 1:7 - The decrees of God concerning this land are clear. It is a land of promise, and any nation who possesses it will serve God or be swept off when the fullness of his wrath comes upon them. The fullness of his wrath comes when they are full of iniquity, willfully rebelling with no intent to repent. This land is special above all other lands. Those who live here will serve God or be swept off, that is the everlasting decree of God. His wrath will not come until the people of the land are full of sin. This knowledge is given to you, gentiles, to read these words and know the decrees of God, that you may repent and not continue in sin and bring the fullness of God’s wrath on you as the previous occupants of the land have done. This is a precious land, and whatever nation lives here will be free from slavery, captivity, and from all other nations under Heaven so long as they serve the God of the land, who is Jesus Christ, who has been revealed to you by the things we have written.
The book is also full of movement and journey, typically small groups of families and friends, led by God to the promised land itself or to a more secure location to escape from enemies or slavery. The journeys began with a dream, vision, or the voice of God (i.e., revelation), and in orderly fashion guided by him while literally not knowing what was over the next horizon. Twice the Jaredites mistakenly thought they had arrived at their destination only to be prodded on to continue their journey. Revelation and faith were key to making the spindles of the Liahona work. Sin and rebellion brought the trek to a halt. From the ancient Israelites to the family of Lehi, to the Jaredites to us and everyone in between, the pattern and message is the same. Is there not a type in this message? As Alma taught his son Helaman (Alma 17:15-17):
15. I want to tell you more about the ball or director, which our ancestors called the Liahona (which interpreted means compass), and the Lord prepared it for them. There is no one that has created anything as unique as this compass or that could duplicate it. It was created to direct our ancestors along their journey, and it worked according to their faithfulness to God. If they had faith that the spindles could point the way they should go, it was done. This was a miracle for them, and God did many miracles for them, day by day. These miracles seemed simple and small, yet they did wonderful works on their behalf. Nevertheless, they were still lazy and forgot to exercise faith and diligence, and then the wonderful works ceased, and it hindered their journey. They lingered in the wilderness, and did not travel a direct course, and were hungry and thirsty because of their neglect.
16. I want you to understand, my son, that these lessons are a type of that which is spiritual. Even as our ancestors did not give heed to this compass (representing the temporal) they did not prosper or progress in their physical journey, which is a lesson in how spiritual progression works as well. It is easy to heed the word of Christ, which will direct you along a straight course to eternal bliss, just as it was for our ancestors to follow this compass which pointed them a straight course to the promised land. Is this not an important lesson? Just as surely as this compass brought our ancestors, if they followed its course, to the promised land so will the words of Christ, if we follow their course, carry us beyond this vale of sorrow to a far better land of promise.
17. Do not be neglectful, my son, because of the simpleness of the way, for so it was for our forefathers. As it was prepared for them if they would but simply look, and live, so it is with us. The way is prepared, and if we look, we may live forever. My son, take care of these sacred items, and look to God and live. Go to this people, preach the word of Christ, and do not neglect all that is sacred you have been entrusted with. My son, farewell.