3 Nephi 1:1

Now it came to pass that the ninety and first year had passed away

and it was six hundred years from the time that Lehi left Jerusalem;

and it was in the year that Lachoneus was the chief judge

and the governor over the land.

3 Nephi 1:2

And Nephi, the son of Helaman, had departed out of the land of Zarahemla,

giving charge unto his son Nephi, who was his eldest son,

concerning the plates of brass, and all the records which had been kept,

and all those things which had been kept sacred

from the departure of Lehi out of Jerusalem.

3 Nephi 1:3

Then he departed out of the land,

and whither he went, no man knoweth;

and his son Nephi did keep the records in his stead,

yea, the record of this people.