Then shall the Kings and the princes enter in at the gates of this citie, and shall sit vpon the throne of Dauid, and shall ride vpon charets, and vpon horses, both they and their princes, the men of Iudah, and the inhabitants of Ierusalem: and this citie shall remaine for euer.
Jeremiah 17:23 But they obeied not, neither inclined their eares, but made their neckes stiffe and would not heare, nor receiue correction.
Jeremiah 17:24 Neuerthelesse if ye will heare me, sayth the Lord, and beare no burden through the gates of the citie in the Sabbath day, but sanctifie ye Sabbath day, so that ye do no worke therein,
Jeremiah 17:25 Then shall the Kings and the princes enter in at the gates of this citie, and shall sit vpon the throne of Dauid, and shall ride vpon charets, and vpon horses, both they and their princes, the men of Iudah, and the inhabitants of Ierusalem: and this citie shall remaine for euer.
Jeremiah 17:26 And they shall come from the cities of Iudah, and from about Ierusalem, and from the land of Beniamin, and from the plaine, and from the mountaines, and from the South, which shall bring burnt offrings, and sacrifices, and meate offrings, and incense, and shall bring sacrifice of prayse into the house of the Lord.
Jeremiah 17:27 But if ye will not heare me to sanctifie the Sabbath day, and not to beare a burden nor to go through the gates of Ierusalem in the Sabbath day, then will I kindle a fire in the gates thereof, and it shall deuoure the palaces of Ierusalem, and it shall not be quenched.
The verse centers on "shall", "kings", "princes", "enter", "gates", "citie", and "vpon". It is saying that the verse draws attention to "shall" and "kings", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 24's "Neuerthelesse if ye will heare me sayth..." into verse 26's "And they shall come from the cities...", so "shall" and "kings" belong inside that flow. In Jeremiah context, the local focus is covenant, worship, and faithfulness.
A plain takeaway is to answer the verse's own emphasis on "shall" and "kings" with trust shaped by these words, not by a vague optimism outside the passage.