Passage
Thus saith the Lord: if my covenant, with the day can be made void, and my covenant with the night, that there should not be day and night in their season:
Thus saith the Lord: if my covenant, with the day can be made void, and my covenant with the night, that there should not be day and night in their season:
Jeremiah 33:18 Neither shall there be cut off from the priests and Levites a man before my face to offer holocausts, and to burn sacrifices, and to kill victims continually.
Jeremiah 33:19 And the word of the Lord came to Jeremiah, saying:
Jeremiah 33:20 Thus saith the Lord: if my covenant, with the day can be made void, and my covenant with the night, that there should not be day and night in their season:
Jeremiah 33:21 Also my covenant with David my servant may be made void, that he should not have a son to reign upon his throne, and with the Levites and priests my ministers.
Jeremiah 33:22 As the stars of heaven cannot be numbered, nor the sand of the sea be measured: so will I multiply the seed of David my servant, and the Levites my ministers.
The verse centers on "thus", "saith", "lord", "covenant", "void", "night", and "should". It is saying that the verse draws attention to "thus" and "saith", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 19's "And the word of the Lord came..." into verse 21's "Also my covenant with David my servant...", so "thus" and "saith" 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 "thus" and "saith" with trust shaped by these words, not by a vague optimism outside the passage.