Numbers 8:26

26 They may assist their brothers in performing their duties at the tent of meeting, but they themselves must not do the work. This, then, is how you are to assign the responsibilities of the Levites.”

Read Numbers 8:26 Using Other Translations

But shall minister with their brethren in the tabernacle of the congregation, to keep the charge, and shall do no service. Thus shalt thou do unto the Levites touching their charge.
They minister to their brothers in the tent of meeting by keeping guard, but they shall do no service. Thus shall you do to the Levites in assigning their duties."
After retirement they may assist their fellow Levites by serving as guards at the Tabernacle, but they may not officiate in the service. This is how you must assign duties to the Levites.”

What does Numbers 8:26 mean?

John Gill's Exposition of the Bible
Numbers 8:26

But shall minister with their brethren in the tabernacle of
the congregation
By giving advice, instructing younger Levites, and doing lighter service. Jarchi says, they shall return to shutting of doors, singing and loading wagons; but the last especially seems too burdensome: the ministry of such is explained by the next clause, to keep the charge;
of the tabernacle, to watch and observe that no stranger or unclean person enter into it; and this they were capable of when at the age of fifty, and upwards: and shall do no service;
heavy and laborious: thus thou shall do unto the Levites touching their charge;
dismiss them from service when at such an age, or however make their service easier; for this respects ancient men, as Aben Ezra notes; though it may include both their entrance on their work, and their cessation from it.

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