Here Yahweh speaks of the armies that he is using to punish his people as being his "sword." His"sword" is described here as if it were a large animal that attacked and devoured the people. AT: "for the armies are my sword that I am using to punish you" or "for I am sending the destroying armies to attack you" (See: [[rc://en/ta/man/translate/figs-metaphor]] and [[rc://en/ta/man/translate/figs-personification]])
"So be ashamed of your tiny harvest because Yahweh is angry with you." Here the word "gain" does not mean a large amount of something, but refers to a small amount.