Bede

But after the wall was built, etc. And in a spiritual sense, wherever the wall of the Church may be built, gathering new peoples to the faith, or correcting those who have strayed, immediately the gates of regular discipline should be set up, so that the ancient enemy, who goes about like a roaring lion (I Peter V), may not anywhere break into the fold of the faithful. The gatekeepers, singers, and Levites must be reviewed, who guard the same gates; it is clear that the role of these pertains to all holy teachers. …

Commentary on Ezra and Nehemiah ↗