TSK · Numbers 4:23

From thirty years old and upward even until fifty years old, all that enter into the host, to do the work in the tabernacle of the congregation.

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.

For by the last words of David the Levites [were] numbered from twenty years old and above:

¶ For we know that the law is spiritual: but I am carnal, sold under sin.

By the word of truth, by the power of God, by the armour of righteousness on the right hand and on the left,

For the flesh lusteth against the Spirit, and the Spirit against the flesh: and these are contrary the one to the other: so that ye cannot do the things that ye would.

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

Thou therefore endure hardness, as a good soldier of Jesus Christ.