3 Nephi 7

Even after the miracle of destroying the Gadianton robbers out of their midst and returning to righteouness and prosperity, the people again began to return to pride, materialism, and immorality. We see during righteousness and obeying the laws of the land based upon the laws of God, prosperity always seems to come. But we learn as wickedness as described above again enters into the hearts of men, prosperity ends, government fails, anarchy follows, and people become governed by their own (the natural man) desires and laws. I find it somewhat painful to continue to read this historical pattern for again they -

"...sought for happiness in doing iniquity, which thing is contrary to the nature of that righteousness which is in our great and Eternal Head." (Book of Mormon | Helaman 13:38)

No question that Satan had a great influence in this decline for Mormon teaches us -

"Now the cause of this iniquity of the people was this—Satan had great power, unto the stirring up of the people to do all manner of iniquity, and to the puffing them up with pride, tempting them to seek for power, and authority, and riches, and the vain things of the world." (Book of Mormon | 3 Nephi 6:15)

And even worse, during this period -

"...there began to be men inspired from heaven and sent forth, standing among the people in all the land, preaching and testifying boldly of the sins and iniquities of the people, and testifying unto them concerning the redemption which the Lord would make for his people, or in other words, the resurrection of Christ; and they did testify boldly of his death and sufferings.
21 Now there were many of the people who were exceedingly angry because of those who testified of these things; and those who were angry were chiefly the chief judges, and they who had been high priests and lawyers; yea, all those who were lawyers were angry with those who testified of these things." (Book of Mormon | 3 Nephi 6:20 - 21)

And so -

"...many of those who testified of the things pertaining to Christ who testified boldly, who were taken and put to death secretly by the judges..." (Book of Mormon | 3 Nephi 6:23)

The truth always seems to hurt the worst. But even in these wicked circumstances -

"...Nephi did cry unto the people...and he did preach unto them repentance and remission of sins." (Book of Mormon | 3 Nephi 7:23)

It is at this point in history that Mormon teaches and important doctrine -

"Now I would have you to remember also, that there were none who were brought unto repentance who were not baptized with water.
25 Therefore, there were ordained of Nephi, men unto this ministry, that all such as should come unto them should be baptized with water, and this as a witness and a testimony before God, and unto the people, that they had repented and received a remission of their sins." (Book of Mormon | 3 Nephi 7:24 - 25)

There are many that feel that if they repent they will be forgiven. In my mind, this may be true. But forgiveness alone does not suggest pardon or a waiver of justice. The only way man can receive a remission of sins is through baptism. This requirement cannot be waived. For it is upon baptism that we are privileged to receive the Gift of the Holy Ghost for these are they that are -

"...received unto baptism, and were wrought upon and cleansed by the power of the Holy Ghost..." (Book of Mormon | Moroni 6:4)

Mormon makes it clear that this is the pattern to receive the blessings of mercy and the atonement.