Charles Ellicott Commentary Jeremiah 20:5

"Moreover I will give all the riches of this city, and all the gains thereof, and all the precious things thereof, yea, all the treasures of the kings of Judah will I give into the hand of their enemies; and they shall make them a prey, and take them, and carry them to Babylon." — Jeremiah 20:5 (ASV)

All the strength. —i.e., the treasure or “substance” of the city.