Jamieson, Fausset and Brown on 1 Chronicles 26:20

20. of the Levites, Ahijah--The heading of this section is altogether strange as it stands, for it looks as if the sacred historian were going to commence a new subject different from the preceding. Besides, "Ahijah, whose name occurs after" the Levites, is not mentioned in the previous lists. It is totally unknown and is introduced abruptly without further information; and lastly, Ahijah must have united in his own person those very offices of which the occupants are named in the verses that follow. The reading is incorrect. The Septuagint has this very suitable heading, "And their Levitical brethren over the treasures," &c. [Bertheau]. The names of those who had charge of the treasure chambers at their respective wards are given, with a general description of the precious things committed to their trust. Those treasures were immense, consisting of the accumulated spoils of Israelitish victories, as well as of voluntary contributions made by David and the representatives of the people.

1Ch 26:29-32. Officers and Judges.