'Office' in the Bible

All of those who are chosen for gatekeepers at the thresholds are two hundred and twelve; they are in their villages, by their genealogy; they whom David and Samuel the seer appointed in their office.

For in office are the four chiefs of the gatekeepers, they are Levites, and they have been over the chambers, and over the treasuries of the house of God,

And Mattithiah, of the Levites (he is the first-born to Shallum the Korahite), is in office over the work of the pans.

And David distributeth them, and Zadok of the sons of Eleazar, and Ahimelech of the sons of Ithamar, according to their office in their service;