King Benjamin taught how to be engaged in the work of God. “I tell you these things that ye may learn wisdom; that ye may learn that when ye are in the service of your fellow beings ye are only in the service of your God.” (Mosiah 2: 17.) Service to others, and charity to others, not judging the begger but relieving their suffering, these were the hallmarks of King Benjamin’s religion. He practiced his faith by helping others. He tied together forgivness of your sins with helping those who are in need: “For the sake of retaining a remission of your sins from day to day, that ye may walk guiltless before God– I would that ye should impart of your substance to the poor, every man according to that which he hath, such as feeding the hungry, clothing the naked, visiting the sick and administering to their relief, both spiritually and temporally, according to their wants.” (Mosiah 4: 26.)
King Benjamin is teaching the ideal. This is his pattern of righteousness for his people. If they follow this sermon, there will be unity and no poor among them.
This single focus on helping others was to the exclusion of a lengthy discourse on evil. In his great sermon he only briefly discusses evil, focusing instead on avoiding contention. He taught that contention allowed an evil spirit to enter in, at which point other bad things would follow. (See Mosiah 2: 32-33.) He admonished you to return what you borrow from your neighbor. (Mosiah 4: 28.)
To cover the topic of evil, he wisely counseled as follows: “I cannot tell you all the things whereby ye may commit sin for there are divers ways and means, even so many that I cannot number them.” (Mosiah 4: 29.) That frank assessment by King Benjamin is beyond the wisdom of a young person to grasp. It reflects the lifelong contemplation of an aging king, not the clever fiction of a young Joseph Smith. It is one of the reasons I do not believe Joseph Smith authored the Book of Mormon and one of the proofs it reflects a greater wisdom than was his when the book was first printed. King Benjamin was unwilling to give a lengthy list of what not-to-do, because the list would be endless. Instead he tells what ought to be done to avoid it in an ideal society.
Likewise, the Lord was not concerned with all the temptations which befell Him. Instead, He chose to give them “no heed” (D&C 20: 22), staying focused upon what good He could do to His fellow man. Had it been followed, King Benjamin’s blueprint would have made a better Nauvoo. The fact it wasn’t is proof Joseph Smith did not author the Book of Mormon, nor possess the society-organizing wisdom of King Benjamin. But, then again, Joseph died at 38, and King Benjamin lived into old age.