EZR 3:8

8 Then in the second month of the second year after they came to the house of God in Jerusalem, Zerubbabel son of Shealtiel, Jeshua son of Jozadak, the rest of the priests, the Levites, and those who came from captivity back to Jerusalem began the work. They assigned the Levites twenty years old and older to oversee the work of Yahweh's house.