18 If any meat of the fellowship offering is eaten on the third day, the one who offered it will not be accepted. It will not be reckoned to their credit, for it has become impure; the person who eats any of it will be held responsible.

Matthew Henry's Commentary on Leviticus 7:18

Commentary on Leviticus 7:11-27

(Read Leviticus 7:11-27)

As to the peace-offerings, in the expression of their sense of mercy, God left them more at liberty, than in the expression of their sense of sin; that their sacrifices, being free-will offerings, might be the more acceptable, while, by obliging them to bring the sacrifices of atonement, God shows the necessity of the great Propitiation. The main reason why blood was forbidden of old, was because the Lord had appointed blood for an atonement. This use, being figurative, had its end in Christ, who by his death and blood-shedding caused the sacrifices to cease. Therefore this law is not now in force on believers.