1 Chronicles 4:39

And they went to the entrance of Gedor, even unto the east side of the valley, to seek pasture for their flocks.

The verse stands in the genealogies division of Chronicles, in the opening section that runs from 1 Chronicles 1 to 4. As part of that book it presumes acquaintance with the earlier books of the Bible and adds fresh facts omitted from Samuel and Kings, while having almost nothing to say about the northern kingdom. Such family records were preserved because after the exile they were required to restore the land to its hereditary owners and to assign the temple service to those to whom it hereditarily belonged.