The differences in the King James text were made to make it easier to read in English and are not significant, therefore the text is not quoted.
These verses refer to those who come against Judah in the last days, the Gentile nations in the battle of Armageddon. The Lord will come to the aid of his people and plead their cause. The Prophet Amos foretold also in these words:
9 Proclaim ye this among the Gentiles; Prepare war, wake up the mighty men, let all the men of war draw near; let them come up: 10 Beat your plowshares into swords, and your pruninghooks into spears: let the weak say, I am strong.
11 Assemble yourselves, and come, all ye heathen, and gather yourselves together round about: thither cause thy mighty ones to come down, O LORD.
12 Let the heathen be wakened, and come up to the valley of Jehoshaphat: for there will I sit to judge all the heathen round about. 13 Put ye in the sickle, for the harvest is ripe: come, get you down; for the press is full, the fats overflow; for their wickedness is great. 14 Multitudes, multitudes in the valley of decision: for the day of the LORD is near in the valley of decision. 15 The sun and the moon shall be darkened, and the stars shall withdraw their shining.
16 The LORD also shall roar out of Zion, and utter his voice from Jerusalem; and the heavens and the earth shall shake: but the LORD will be the hope of his people, and the strength of the children of Israel.
17 So shall ye know that I am the LORD your God dwelling in Zion, my holy mountain: then shall Jerusalem be holy, and there shall no strangers pass through her any more. [Joel 3:9–17; see also Zechariah 12–14; D&C 45:42–53]