1 Chronicles 23:27
For by the last words of David the Levites were numbered from twenty years old and above: (1 Chronicles 23:27)
Twenty years.
 Compare v. 24 and 2 Chron. 31:17. Some think that David now changed the age limit to meet the new conditions.
Last words of David.
Some suppose “the last words of David” to constitute an historical work drawn up in the latter years of David’s reign. This cannot be proved.