From thirty years old and upward until fifty years old shall you number them; all that enter in to perform the service, to do the work in the tabernacle of meeting.
For the flesh lusts against the Spirit, and the Spirit against the flesh: and these are contrary the one to the other: so that you cannot do the things that you would.
Who goes to warfare any time at his own expense? who plants a vineyard, and eats not of the fruit thereof? or who feeds a flock, and eats not of the milk of the flock?
These were the sons of Levi by their fathers’ houses; even the heads of their fathers’ houses, as they were counted individually by the number of their names, that did the work for the service of the house of the LORD, from the age of twenty years and upward.