Jeremiah 33:18

Likewise, the Levitical priests would resume functioning and continue to do so forever. [Note: This verse and the ones that follow are the only references to the restoration of the legitimate priesthood in the book.] They would offer sacrifices of worship continually (in the millennial kingdom). The burnt and grain (or meal) offerings were primarily for worship rather than to remove the defilement of sin (cf. Leviticus 1-2). In Jeremiah’s day, the priesthood was corrupt, and it may even have included non-Levitical priests (cf. Jeremiah 6:13; Jeremiah 19:1; Jeremiah 26:10-11). The lack of legitimate priests was a problem in the early years of the restoration community (cf. Ezra 8:15).

In the Millennium there will be a restoration of Levitical priests, though instead of looking forward to the coming of the ultimate Sacrifice, the worshippers will look back to it. The Levitical priests will worship God under the New Covenant. The Old (Mosaic) Covenant came to an end at the Cross. A Davidic king, Jesus Christ, will also provide leadership under the New Covenant. Therefore, both the royal and priestly leadership of Israel, in the future, will resume what Israel formerly experienced under the Mosaic Covenant.