Charles Ellicott Commentary Nehemiah 13:19

"And it came to pass that, when the gates of Jerusalem began to be dark before the sabbath, I commanded that the doors should be shut, and commanded that they should not be opened till after the sabbath: and some of my servants set I over the gates, that there should no burden be brought in on the sabbath day." — Nehemiah 13:19 (ASV)

Some of my servants. —These are several times mentioned as employed in public duty. Here they are used provisionally, to keep out traffickers until the formal appointment of the Levitical guard (Nehemiah 13:22), after which they would be relieved.