Thematic Bible: Irregularities in

He said to them, "Have you not read what David did when he was hungry, and those who were with him: how he entered the house of God and ate the bread of the Presence, which it was not lawful for him to eat nor for those who were with him, but only for the priests?

For the king and his princes and all the assembly in Jerusalem had taken counsel to keep the Passover in the second month-- for they could not keep it at that time because the priests had not consecrated themselves in sufficient number, nor had the people assembled in Jerusalem-- and the plan seemed right to the king and all the assembly. read more.
So they decreed to make a proclamation throughout all Israel, from Beersheba to Dan, that the people should come and keep the Passover to the LORD, the God of Israel, at Jerusalem, for they had not kept it as often as prescribed.

For there were many in the assembly who had not consecrated themselves. Therefore the Levites had to slaughter the Passover lamb for everyone who was not clean, to consecrate it to the LORD. For a majority of the people, many of them from Ephraim, Manasseh, Issachar, and Zebulun, had not cleansed themselves, yet they ate the Passover otherwise than as prescribed. For Hezekiah had prayed for them, saying, "May the good LORD pardon everyone who sets his heart to seek God, the LORD, the God of his fathers, even though not according to the sanctuary's rules of cleanness." read more.
And the LORD heard Hezekiah and healed the people.