'Ministering' in the Bible

We also accept responsibility, as is written in the law, for bringing the firstborn of our sons and our cattle and the firstborn of our herds and of our flocks to the temple of our God, to the priests who are ministering in the temple of our God.

On that day men were appointed over the storerooms for the contributions, first fruits, and tithes, to gather into them from the fields of the cities the portions prescribed by the law for the priests and the Levites, for the people of Judah took delight in the priests and Levites who were ministering.