Leviticus 6:17, 25

It must not be baked with yeast; I have given it as their share of the food offerings presented to me. Like the sin offering and the guilt offering, it is most holy.

“Say to Aaron and his sons: ‘These are the regulations for the sin offering: The sin offering is to be slaughtered before the LORD in the place the burnt offering is slaughtered; it is most holy.