The Passover lambs were slaughtered, and the priests splashed against the altar the blood handed to them, while the Levites skinned the animals.
References for 2 Chronicles 35:11
They set aside the burnt offerings to give them to the subdivisions of the families of the people to offer to the LORD, as it is written in the Book of Moses. They did the same with the cattle.
They roasted the Passover animals over the fire as prescribed, and boiled the holy offerings in pots, caldrons and pans and served them quickly to all the people.
References for 2 Chronicles 35:13
After this, they made preparations for themselves and for the priests, because the priests, the descendants of Aaron, were sacrificing the burnt offerings and the fat portions until nightfall. So the Levites made preparations for themselves and for the Aaronic priests.
References for 2 Chronicles 35:14
The musicians, the descendants of Asaph, were in the places prescribed by David, Asaph, Heman and Jeduthun the king’s seer. The gatekeepers at each gate did not need to leave their posts, because their fellow Levites made the preparations for them.
References for 2 Chronicles 35:15
So at that time the entire service of the LORD was carried out for the celebration of the Passover and the offering of burnt offerings on the altar of the LORD, as King Josiah had ordered.
The Israelites who were present celebrated the Passover at that time and observed the Festival of Unleavened Bread for seven days.
The Passover had not been observed like this in Israel since the days of the prophet Samuel; and none of the kings of Israel had ever celebrated such a Passover as did Josiah, with the priests, the Levites and all Judah and Israel who were there with the people of Jerusalem.
This Passover was celebrated in the eighteenth year of Josiah’s reign.
After all this, when Josiah had set the temple in order, Necho king of Egypt went up to fight at Carchemish on the Euphrates, and Josiah marched out to meet him in battle.
References for 2 Chronicles 35:20
But Necho sent messengers to him, saying, “What quarrel is there, king of Judah, between you and me? It is not you I am attacking at this time, but the house with which I am at war. God has told me to hurry; so stop opposing God, who is with me, or he will destroy you.”
References for 2 Chronicles 35:21