Bede

In the days of Joachim there were priests, etc. However, after providing the succession of chief priests, a catalogue of the lesser priests and Levites who existed during their times is also added, so that we might know that, when the number of citizens in Jerusalem increased abundantly, the group of priests and Levites was also distinguished and noble, sufficient for the ministries of the temple and altar, for confessing and praising God, for the guardianship of the same temple and city, and for instructing the people. …

Commentary on Ezra and Nehemiah ↗