Sacrifice

In verse 9 of the 1st book of Nephi, the term Sacrifice, is there to remind us that they were still living the Law of Moses, including animal sacrifices, to symbolize of the coming Atonement of Christ.  Nephi's time is during the Old Testament times. 

And for further note:  This part of the Book of Mormon as being Old Testament, it's important to remember tha tthe Book of Mormon gives us a more accurate underestanding of Old Testament teachings about Christ than our current version of the Old Testament does.