1 Chronicles 23:3

And the Levites thirty years old and above were counted, and their number according to their head count for the men [was] thirty-eight thousand.

1 Chronicles 23:24

These [were] the sons of Levi according to the house of their fathers, the heads of the {families}, according to their enrollment, by the number of the names, according to their head count, [who were to] do the work of the service of the house of Yahweh, from twenty years old and above.

Numbers 4:2-49

"{Take a census} of the descendants of Kohath from the midst of the descendants of Levi, according to their clans and {their families},

Treasury of Scripture Knowledge

Summary

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

Thirty and eight

General references

Bible References

The levites

Numbers 4:2
"{Take a census} of the descendants of Kohath from the midst of the descendants of Levi, according to their clans and {their families},

Thirty and eight

Numbers 4:48
the {ones counted} were eighty thousand five hundred and eighty.

General references

Numbers 4:35
from {those thirty years old} and above until {fifty years old}; everyone who comes to the service to work in the tent of assembly,