Albert Barnes Commentary Joshua 21:42

"These cities were every one with their suburbs round about them: thus it was with all these cities." — Joshua 21:42 (ASV)

After this verse, the Septuagint introduces a passage (in part a repetition from Joshua 19:49-50), recording the grant of a special inheritance to Joshua, and also that he buried at Timnath-serah the flint-knives with which he had circumcised (Joshua 5:2, note) the people after the passage of Jordan. The latter statement, which has the authority of the Septuagint only, is a Jewish legend of early date.