Ezra 3:8 NIV

8 In the second month1 of the second year after their arrival at the house of God in Jerusalem, Zerubbabel2 son of Shealtiel, Jeshua son of Jozadak and the rest of their brothers (the priests and the Levites and all who had returned from the captivity to Jerusalem) began the work, appointing Levites twenty3 years of age and older to supervise the building of the house of the LORD.

References for Ezra 3:8