2 Chronicles 25:5

5 Amaziah called the people of Judah together and assigned them according to their families to commanders of thousands and commanders of hundreds for all Judah and Benjamin. He then mustered those twenty years old or more and found that there were three hundred thousand men fit for military service, able to handle the spear and shield.

Read 2 Chronicles 25:5 Using Other Translations

Moreover Amaziah gathered Judah together, and made them captains over thousands, and captains over hundreds, according to the houses of their fathers, throughout all Judah and Benjamin: and he numbered them from twenty years old and above, and found them three hundred thousand choice men, able to go forth to war, that could handle spear and shield.
Then Amaziah assembled the men of Judah and set them by fathers' houses under commanders of thousands and of hundreds for all Judah and Benjamin. He mustered those twenty years old and upward, and found that they were 300,000 choice men, fit for war, able to handle spear and shield.
Then Amaziah organized the army, assigning generals and captains for all Judah and Benjamin. He took a census and found that he had an army of 300,000 select troops, twenty years old and older, all trained in the use of spear and shield.

What does 2 Chronicles 25:5 mean?

John Gill's Exposition of the Bible
2 Chronicles 25:5

Moreover Amaziah gathered Judah together
The inhabitants thereof:

and made them captains over thousands, and captains over hundreds,
according to the houses of their fathers, throughout all Judah and
Benjamin;
he divided the people, according to their families throughout his kingdom, into thousands and hundreds, and out of their respective families appointed captains over them:

and he numbered them from twenty years old and above;
the usual age men were numbered at for war, to the fiftieth, according to Josephus; the Roman law F1 obliged none to be soldiers after fifty, nor might any be dismissed before F2; the age of military men with the Romans was from seventeen to forty six, or, as some, forty five; but with the Persians from twenty as here to fifty F3:

and found them three hundred thousand choice men, able to go forth to
war, that could handle spear and shield;
which shows that their number was greatly decreased since the times of Jehoshaphat, ( 2 Chronicles 17:14-18 ) , occasioned by the wars under Jehoram, Ahaziah, and Joash; some copies of the Vulgate Latin F4 have only 30,000.


FOOTNOTES:

F1 Seneca de Brevitate Vitae, c. 20.
F2 Liv. Hist. l. 42. c. 33.
F3 Alex. ab. Alex. Genial. Dier. l. 1. c. 20.
F4 Ed. of Sixtus V. the Lovain and MSS. in James's Corruption of the Fathers, p. 295.
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