en_tn/1ch/23/03.md

The Levites who were thirty years old and older were counted

This can be stated in active form. Alternate translation: "Some of David's men counted the Levites who were 30 years old and older" (See: rc://en/ta/man/jit/figs-activepassive)

they numbered thirty-eight thousand

"there were 38,000 of them" (See: rc://en/ta/man/jit/translate-numbers)