2 Chronicles 35:11

Then the king commanded all the people saying, “Celebrate the Passover to Yahweh your God as it is written in this book of the covenant.”

But the priests were too few, so that they were unable to skin all the burnt offerings; therefore their brothers the Levites helped them until the work was completed and until the other priests had set themselves apart as holy. For the Levites were more upright of heart to set themselves apart as holy than the priests.

For the priests and the Levites had cleansed themselves together; all of them were clean. Then they slaughtered the Passover lamb for all the exiles, both for their brothers the priests and for themselves.