Taking the cup and making the nations drink it is a symbolic act, and it is very unlikely that Jeremiah actually travelled to kings and made them drink from a cup.1 He probably carried out this instruction from the Lord by preaching the message from the temple in Jerusalem and possibly even held a cup in his hands as a symbol of the Lord’s judgment.
The more important point is not the specifics of how Jeremiah carried out his task, but rather that the mere announcement of the Lord’s judgment already set judgment in motion. The Lord will definitely do what he says. Judgment is coming and the nations will drink and they will stagger and be crazed.
The Lord’s judgment will cause nations to behave like drunk people who have no control over their actions or even their thoughts.2 The Lord will carry out this judgment by sending a sword among them. The sword is often used in Jeremiah to speak of military invasion and in this case is a reference to the powerful Babylonian army.
16 They shall drink and stagger and be crazed because of the sword that I am sending among them.”