TSK · Numbers 4:3

From twenty years old and upward, all that are able to go forth to war in Israel: thou and Aaron shall number them by their armies.

And they shall keep his charge, and the charge of the whole congregation before the tabernacle of the congregation, to do the service of the tabernacle.

From thirty years old and upward even unto fifty years old shalt thou number them, every one that entereth into the service, to do the work of the tabernacle of the congregation.

From thirty years old and upward even unto fifty years old, every one that came to do the service of the ministry, and the service of the burden in the tabernacle of the congregation,

[Seemeth it but] a small thing unto you, that the God of Israel hath separated you from the congregation of Israel, to bring you near to himself to do the service of the tabernacle of the LORD, and to stand before the congregation to minister unto them?

Their brethren also the Levites [were] appointed unto all manner of service of the tabernacle of the house of God.

¶ These [were] the sons of Levi after the house of their fathers; [even] the chief of the fathers, as they were counted by number of names by their polls, that did the work for the service of the house of the LORD, from the age of twenty years and upward.

And the pattern of all that he had by the spirit, of the courts of the house of the LORD, and of all the chambers round about, of the treasuries of the house of God, and of the treasuries of the dedicated things:

Both to the genealogy of the priests by the house of their fathers, and the Levites from twenty years old and upward, in their charges by their courses;

And Jesus himself began to be about thirty years of age, being (as was supposed) the son of Joseph, which was [the son] of Heli,

¶ Finally, my brethren, be strong in the Lord, and in the power of his might.

¶ This [is] a true saying, If a man desire the office of a bishop, he desireth a good work.