Numbers 8:24

“This applies to the Levites: Men twenty-five years of age or older shall enter to perform the service in the work at the Tent of Meeting.
BSB · Berean Standard Bible
This is it that belongeth unto the Levites: from twenty and five years old and upward they shall go in to wait upon the service of the tabernacle of the congregation:

Note to…: Heb. to war the warfare of, etc

KJV · King James Version
“This is what is assigned to the Levites: from twenty-five years old and upward they shall go in to wait on the service in the work of the Tent of Meeting;
WEB · World English Bible
This is that which belongeth unto the Levites: from twenty and five years old and upward they shall go in to wait upon the service in the work of the tent of meeting:
ASV · American Standard Version

Related passages

From the Treasury of Scripture Knowledge, grouped by the word they explain.

from twenty
In ch. 4:3, the Levites are appointed to the service of the tabernacle at the age of 30 years; and in 1 Ch 23:24, they are ordered to commence their work at 20 years of age. In order to reconcile this apparent discrepancy, it is to be observed, 1. At the time of which Moses speaks in ch. 4:3, the Levitical service was exceedingly severe, and consequently required full grown, robust men, to perform it; the age of 30 was therefore appointed as the period for commencing this service, the weightier part of which was probably there intended. 2. In this place God seems to speak of the service in a general way: hence the age of 25 is fixed. 3. In David's time, and afterwards, in the fixed tabernacle and temple, the laboriousness of the service no longer existed, and hence 20 years was the age appointed.
Numbers 4:3, 23; 1 Chronicles 23:3, 24–27; 1 Chronicles 28:12, 13
wait upon
Heb. war the warfare of, etc.
1 Corinthians 9:7; 2 Corinthians 10:4; 1 Timothy 1:18; 1 Timothy 6:12; 2 Timothy 2:3–5