This is symbolic language to indicate that the angel was sent from Yahweh in heaven to judge the people on the earth. (See: [[rc://en/ta/man/translate/writing-symlanguage]])
The angel holding a sword in his hand is a symbolic action that shows he is ready to attack Jerusalem. This is symbolic, because the judgment was sickness. AT: "holding a sword in his hand as if ready to attack Jerusalem" (See: [[rc://en/ta/man/translate/translate-symaction]])
David uses this question to emphasize that his is the one who sinned by counting the people. AT: "I am the one who commanded that the army be numbered." (See: [[rc://en/ta/man/translate/figs-rquestion]])
# But these sheep
David speaks of the people of Israel as if they were sheep, who are known for trusting and following their leader. (See: [[rc://en/ta/man/translate/figs-metaphor]])
# what have they done?
David uses this question to asks God not to punish the people. This rhetorical question can be translated as a statement. AT: "they certainly have done nothing that deserves punishment." (See: [[rc://en/ta/man/translate/figs-rquestion]])