Jeremiah 33:21
Then may also my covenant be broken with David my servant, that he should not have a son to reign upon his throne; and with the Levites the priests, my ministers. Then may also my covenant be broken with David my servant, that he should not have a son to reign upon his throne; and with the Levites the priests, my ministers.
The verse stands in the part of Jeremiah after chapter 20 where the chapters are not in chronological order. In the chronological order of Jeremiah's experiences in Judah, chapter 33 comes late, after chapters 27, 28, 21, 34, 37 and 32, with its place fixed by dates given in Jeremiah itself. The prophecies were displaced from chronological order when the manuscript rolls were gathered into one book, and this verse belongs late in Jeremiah's work in Judah, after chapter 37 and before chapter 38. The chapter belongs to prophecies of restoration under Christ. As one of the Messianic prophecies in Jeremiah 22-39, the verse looks through the restoration from Babylon to the more glorious restoration under Christ Jesus the Lord.
The verse belongs to a prophecy about Israel's gathering and restoration, occurring at the same time as the promises of a new spirit and deliverance. That restoration is fulfilled for living Israel, meaning the living saints of every nation, just before the resurrection of the just at the commencement of the day of the Lord. The promises concerning Israel in the verse are subject to the broader principle that God's promises to nations depend on obedience, even when no condition is stated alongside each promise. Israel's identity and covenant promises in the verse are fulfilled in the promised seed. The promised restoration of Israel includes the children of promise from all ages, rather than only a national return of living Jewish descendants. The Levites' place in God's covenant promises will be preserved, in that those who were Levites will officiate in the heavenly Jerusalem.
Faithful Israel serves as a type of Israel under the new covenant. God's covenant with David and with the Levites the priests is secure and sure and will not fail, as dependable as the regular return of day and night described in the surrounding verses. God's word accomplishes the purpose for which he sends it, and people may fail to receive the promises through doubt and unbelief while the promises themselves remain true. The enduring covenant of day and night measures the faithfulness of God's call to turn from sin and follow righteousness and truth.