From a site with LDS humour, I believe, though I heard of this so long ago that I can't remember.
When Latter-day Saint missionaries talk to interested nonmembers and explain their faith, they often leave them with a copy of the Book of Mormon and some suggestions for passages to read.
Common passages include Moroni 10:3–5 (Moroni's promise to future readers how they can know whether the book is true) and 3 Nephi 11 (where Jesus appears to the Nephites). Another very well-known scripture among Latter-day Saints is 1 Nephi 3:7, where Nephi tells his father that he
will go and do the things which the Lord hath commanded, for [he knows] that the Lord giveth no commandments unto the children of men, save he shall prepare a way for them that they may accomplish the thing which he commandeth them.
Now, the story goes, a pair of sister missionaries had dropped off a copy of the Book of Mormon at someone's house, but had got mixed up with the reading suggestions and had advised him to read 3 Nephi 3:7—which reads
Or in other words, yield yourselves up unto us, and unite with us and become acquainted with our secret works, and become our brethren that ye may be like unto us—not our slaves, but our brethren and partners of all our substance. (It refers to the Gadianton robbers, a group of people in a "secret combination" to do wickedness; perhaps a bit like the Mafia?)
At any rate, when the sisters got home, they wondered what it said in the scripture they had recommended by mistake, and when they had read what this poor unsuspecting person would read as his first contact with the Book of Mormon, they were sure they had forfeited any chance of talking to him further about the gospel.