Jarom notes that the people kept the law of Moses, honored the Sabbath day, did not prophane, and did not blaspheme. Many of them exercised sufficient faith that they had "communion with the Holy Spirit, which maketh manifest unto the children of men, according to their faith." (v. 4) Jarom notes after saying this that "the laws of the land were exceedingly strict." (v. 5)
One of the outcomes of faith in God and obedience to His commandments is order in society. In our time, there is a creeping permissiveness under which society has come to tolerate almost anything. Strict laws and order in society flow from the righteousness of the people. When the people can't or won't rule their own hearts, they change the law to justify their behavior or ignore the law. Either way, the impact is the same. Society can reach a tipping point where no law enforcement is possible and the nation descends into chaos.
The Book of Mormon was written for our day, and there are repeated promises and warnings that are easy to apply to today.
9...But the word of the Lord was verified, which he spake unto our fathers, saying that: Inasmuch as ye will keep my commandments ye shall prosper in the land.
10 And it came to pass that the prophets of the Lord did threaten the people of Nephi, according to the word of God, that if they did not keep the commandments, but should fall into transgression, they should be destroyed from off the face of the land.