The instructions for the Passover celebration in Exodus 12–13 indicate that lambs should be slaughtered and consumed in diverse family gatherings. Only in Deuteronomy 16 does this celebration become a national festival celebrated in Jerusalem. Notice, for instance, that Deuteronomy does not mention the smearing of blood on the doorpost, which is central to the commemorative observance in Exodus. The differences here have led many to conclude that the Passover was observed among the clans in pre-monarchical Israel and that Deuteronomy reflects a centralizing, reformist vision. This would explain why the reforming Kings Hezekiah and Josiah (2 Kings 23:21–23) lament the fact that the Passover had not been performed “properly” in many years.