Alma 50

With Amalickiah, much like Satan, seeking to bring all the Nephites into bondage and have power over them, Captain Moroni prepared the Nephites to defend themselves, their families, and their religion, wherefore -

"...Moroni did not stop making preparations for war, or to defend his people against the Lamanites; for he caused that his armies should commence in the commencement of the twentieth year of the reign of the judges, that they should commence in digging up heaps of earth round about all the cities, throughout all the land which was possessed by the Nephites.
2 And upon the top of these ridges of earth he caused that there should be timbers, yea, works of timbers built up to the height of a man, round about the cities.
3 And he caused that upon those works of timbers there should be a frame of pickets built upon the timbers round about; and they were strong and high.
4 And he caused towers to be erected that overlooked those works of pickets, and he caused places of security to be built upon those towers, that the stones and the arrows of the Lamanites could not hurt them.
5 And they were prepared that they could cast stones from the top thereof, according to their pleasure and their strength, and slay him who should attempt to approach near the walls of the city."  (Book of Mormon | Alma 50:1 - 5)

Mormon then comments -

"Thus Moroni did prepare strongholds against the coming of their enemies, round about every city in all the land."  (Book of Mormon | Alma 50:6)

There is much wise counsel contained herein, both temporal and spiritual.  First there is great wisdom in being prepared to defend ones freedom, family, liberty, and religion.  But there is also great spiritual counsel to do those things that would prepare oneself so as not to fall to the snares of Satan.