John Gill Commentary 2 Chronicles 2:18

"And he set threescore and ten thousand of them to bear burdens, and fourscore thousand that were hewers in the mountains, and three thousand and six hundred overseers to set the people at work." — 2 Chronicles 2:18 (ASV)

And he set seventy thousand of them
Which is repeated from (2 Chronicles 2:2) , to show how the above number of strangers were disposed of; 70,000 of them bearers of burdens, 80,000 of them hewers of wood, and 3,600 overseers of the workmen, in all 153,600; an emblem of the Gentiles employed in building the spiritual temple, the church, (Zechariah 6:15) .