After twenty-two years of peace, king Laman dies and his son takes a different and more militaristic stance against this people living within his overall lands. The Lamanites prepare for war. Zeniff discovers this because he has been on alert. Twenty-two years earlier he had set guards around his people, and that practice was continued. Thus, the Lamanite preparations were discovered and Zeniff was able to prepare his people.
The catalogue of weaponry is very similar to what was recorded in Mosiah 9:16, but this time the list describes the Lamanite weaponry rather than the Zeniffite list of arms. Because it describes Lamanites, the addition is that the Lamanites have shaved their heads. This suggests that the Lamanites were not typically without hair, but shaved their heads in this military context.
The Zeniffite defense is twofold. The women and children are removed from direct harm’s way and hidden in the wilderness. Then all available males, including old men who were able, were conscripted into the defensive force. This strongly suggests that the Zeniffite people were significantly fewer than the force coming against them.
When Zeniff places the young and old men into ranks, he does so by age, rather than intermingle all of the troops. It is probable that this was to have the ranks of the youngest and the oldest behind those of warrior age, so that they would be used only as a final resort.