The Opening of the Mouth Ceremony was a ritual corpus used to actualize the funerary statuary of a deceased person. During the New Kingdom (1550–1069 BC), the ceremony was also used by the priests at the ipet sut, the most holy, in the great temple to Amen at Waset.

It appears from vignettes from the tombs and especially from The Book of the Dead that the ceremonies involved in the Opening of the Mouth have a much older origin than the New Kingdom. In fact, a similar ceremony, referred to as an offering ritual, occurs throughout the Old Kingdom (2686–2181 BC), in which the statues of the kings were ritualized on a regular basis. It was incorporated into some of the Pyramid Texts as Utterances 20–22 ...