Now the Levites were numbered from the age of thirty years and upward: and their number by their polls, man by man, was thirty and eight thousand.
The Levites were numbered ... thirty and eight thousand - four times their number at the early census taken by Moses, (see the notes at Numbers 4:1-49; Numbers 26:1-65.) It was in all likelihood this vast increase that suggested and rendered expedient that classification, made in the lest year of David's reign, which the present and three subsequent chapters describe.
By their polls, man by man - women and children were not included.