The person whom this verse refers to is Zedekiah, the last king of Israel. Zedekiah was a weak king who listened to the advice of the false prophets and the pro-Egyptian party. In this way he brought a sea of misery over his people. Yet out of respect for his office and his lineage, Jeremiah still calls him the “Lord’s anointed” and “the breath of our nostrils.” He came from the line of David, to whom God had given the promise of an eternal throne (2 Samuel 7:12–16). The throne of David was to Israel like breath is for the body.
Zedekiah was imprisoned in Babel until the day of his death (Jeremiah 52:6–11). In this way, the breath of Israel disappeared. Israel’s national existence came to an end.
20 The breath of our nostrils, the LORD’s anointed, was captured in their pits, of whom we said, “Under his shadow we shall live among the nations.”