After Alma finished his speech to Helaman, he gave him the plates of Nephi, which were the records of their forefathers that went all of the way back to Lehi. I'm sure Helaman was pretty excited. He must have been feeling a bit like this:
And now, my son Helaman, I command you that ye take the records which have been entrusted with me; Alma 37.1
And I also command you that ye keep a record of this people, according as I have done, upon the plates of Nephi, and keep all these things sacred which I have kept, even as I have kept them; for it is for a wise purpose that they are kept. Alma 37.2
Except these plates were brass. Not quite as cool, but they were pretty important, at least according to the prophecy of their forefathers. Apparently these plates would be handed down from one generation to another, and be preserved by God, until every nation knew "the mysteries contained theron". So they were pretty important.
And these plates of brass, which contain these engravings, which have the records of the holy scriptures upon them, which have the genealogy of our forefathers, even from the beginning— 37.3
Behold, it has been prophesied by our fathers, that they should be kept and handed down from one generation to another, and be kept and preserved by the hand of the Lord until they should go forth unto every nation, kindred, tongue, and people, that they shall know of the mysteries contained thereon. 37.4But with great power comes great responsibility. Helaman was put in charge of keeping the record going, and of keeping the plates shiny. Alma insisted that this wasn't a silly detail. God was very particular, and sometimes he would confuse the wise with very small details. So keep them plates shiny, boy!
And now behold, if they are kept they must retain their brightness; yea, and they will retain their brightness; yea, and also shall all the plates which do contain that which is holy writ. 37.5
Now ye may suppose that this is foolishness in me; but behold I say unto you, that by small and simple things are great things brought to pass; and small means in many instances doth confound the wise. 37.6
And the Lord God doth work by means to bring about his great and eternal purposes; and by very small means the Lord doth confound the wise and bringeth about the salvation of many souls. 37.7After telling Helaman how to take care of the plates, Alma just can't help himself. He launches back into his speech, telling him over and over again to keep God's commandments... even though sometimes it's hard to see the reasoning behind them.
O remember, remember, my son Helaman, how strict are the commandments of God. And he said: If ye will keep my commandments ye shall prosper in the land—but if ye keep not his commandments ye shall be cut off from his presence. 37.13
But if ye keep the commandments of God, and do with these things which are sacred according to that which the Lord doth command you, (for you must appeal unto the Lord for all things whatsoever ye must do with them) behold, no power of earth or hell can take them from you, for God is powerful to the fulfilling of all his words. 37.16
Therefore I command you, my son Helaman, that ye be diligent in fulfilling all my words, and that ye be diligent in keeping the commandments of God as they are written. 37.20
Counsel with the Lord in all thy doings, and he will direct thee for good; yea, when thou liest down at night lie down unto the Lord, that he may watch over you in your sleep; and when thou risest in the morning let thy heart be full of thanks unto God; and if ye do these things, ye shall be lifted up at the last day. 37.37
But then things get interesting, and confusing. Apparently God made a special stone that he gave to Gazelem, which shined light on darkness (metaphorically, it seems) so that the wicked secret works of these people (the Jerodites) could be seen. But, even once their abominations were brought out into the open, they still didn't repent. So God destroyed them.
For behold, the Lord saw that his people began to work in darkness, yea, work secret murders and abominations; therefore the Lord said, if they did not repent they should be destroyed from off the face of the earth. 37.22
And the Lord said: I will prepare unto my servant Gazelem, a stone, which shall shine forth in darkness unto light, that I may discover unto my people who serve me, that I may discover unto them the works of their brethren, yea, their secret works, their works of darkness, and their wickedness and abominations. 37.23
And now, my son, these interpreters were prepared that the word of God might be fulfilled, which he spake, saying: 37.24
I will bring forth out of darkness unto light all their secret works and their abominations; and except they repent I will destroy them from off the face of the earth; and I will bring to light all their secrets and abominations, unto every nation that shall hereafter possess the land. 37.25
And now, my son, we see that they did not repent; therefore they have been destroyed, and thus far the word of God has been fulfilled; yea, their secret abominations have been brought out of darkness and made known unto us. 37.26
But Alma wanted Helaman to keep quiet about these wicked things that the Jerodites did, because he was concerned that the people might be attracted to the lifestyle if they found out about it. Alma wanted Helaman to just teach them normal church doctrine, and then everyone would be protected from iniquity.
You know how the police sometimes don't want the media to sensationalize violent crimes, because they are worried about people "copycatting"? Yeah, it's kind of like that.
And now, my son, I command you that ye retain all their oaths, and their covenants, and their agreements in their secret abominations; yea, and all their signs and their wonders ye shall keep from this people, that they know them not, lest peradventure they should fall into darkness also and be destroyed. 37.27
For behold, there is a curse upon all this land, that destruction shall come upon all those workers of darkness, according to the power of God, when they are fully ripe; therefore I desire that this people might not be destroyed. 37.28
Therefore ye shall keep these secret plans of their oaths and their covenants from this people, and only their wickedness and their murders and their abominations shall ye make known unto them; and ye shall teach them to abhor such wickedness and abominations and murders; and ye shall also teach them that these people were destroyed on account of their wickedness and abominations and their murders. 37.29
For behold, they murdered all the prophets of the Lord who came among them to declare unto them concerning their iniquities; and the blood of those whom they murdered did cry unto the Lord their God for vengeance upon those who were their murderers; and thus the judgments of God did come upon these workers of darkness and secret combinations. 37.30
Don't explain to the members of the church why the Jerodites were evil, just keep repeating it, and teach the church to hate sin. Then call the Jerodites sinners -- the people will believe you, even without proof. And, of course, keep the commandments of God.
And now, my son, remember the words which I have spoken unto you; trust not those secret plans unto this people, but teach them an everlasting hatred against sin and iniquity. 37.32
O, remember, my son, and learn wisdom in thy youth; yea, learn in thy youth to keep the commandments of God. 37.35
Then Alma gives Helaman the magic ball of curious workmanship. It has almost as many names as Gandalf: 1.) A ball 2.) director 3.) Liahona 4.) Compass [interpreted]. God made the ball, and it only works if you really believe in it. So remember that if you ever have to use it, Helaman!
And now, my son, I have somewhat to say concerning the thing which our fathers call a ball, or director—or our fathers called it Liahona, which is, being interpreted, a compass; and the Lord prepared it. 37.38
And behold, there cannot any man work after the manner of so curious a workmanship. And behold, it was prepared to show unto our fathers the course which they should travel in the wilderness. 37.39
And it did work for them according to their faith in God; therefore, if they had faith to believe that God could cause that those spindles should point the way they should go, behold, it was done; therefore they had this miracle, and also many other miracles wrought by the power of God, day by day. 37.40And, after warning Helaman not to lose all of his new cool stuff, Alma said goodbye to Helaman and moved on to his next son, Shiblon.
And now, my son, see that ye take care of these sacred things, yea, see that ye look to God and live. Go unto this people and declare the word, and be sober. My son, farewell. 37.47