Ezekiel 44: rules to priests and levites in the new temple

 Ezekiel is in Babylon, the temple is destroyed, however in chapter 44 we read instructions how priests and levites should do their work in the new temple. They sinned when doing their job in the first temple.
They used outsiders (who wasn't circumcised in heart and flesh) to do their job.

6-9 “Tell this bunch of rebels, this family Israel, ‘Message of God, the Master: No more of these vile obscenities, Israel, dragging irreverent and unrepentant outsiders, uncircumcised in heart and flesh, into my Sanctuary, feeding them the sacrificial offerings as if it were the food for a neighborhood picnic. With all your vile obscenities, you’ve broken trust with me, the solemn covenant I made with you. You haven’t taken care of my holy things. You’ve hired out the work to foreigners who care nothing for this place, my Sanctuary. No irreverent and unrepentant aliens, uncircumcised in heart or flesh, not even the ones who live among Israelites, are to enter my Sanctuary.’

As the levites followed idols along with Israel instead of doing the holy job in the temple, they will no longer take care of the Lord's holy things. They will have to serve the people.

10-14 “The Levites who walked off and left me, along with everyone else —all Israel— who took up with all the no-god idols, will pay for everything they did wrong. From now on they’ll do only the menial work in the Sanctuary: guard the gates and help out with the Temple chores—and also kill the sacrificial animals for the people and serve them. Because they acted as priests to the no-god idols and made my people Israel stumble and fall, I’ve taken an oath to punish them. Decree of God, the Master. Yes, they’ll pay for what they’ve done. They’re fired from the priesthood. No longer will they come into my presence and take care of my holy things. No more access to The Holy Place! They’ll have to live with what they’ve done, carry the shame of their vile and obscene lives. From now on, their job is to sweep up and run errands. That’s it.

The chapter contains many directions on how the priest should behave in the new temple, such as:

23 “Their job is to teach my people the difference between the holy and the common, to show them how to discern between unclean and clean.

24 “When there’s a difference of opinion, the priests will arbitrate. They’ll decide on the basis of my judgments, laws, and statutes. They are in charge of making sure the appointed feasts are honored and my Sabbaths kept holy in the ways I’ve commanded.