12 If he offers it for a thanksgiving, then he shall offer with the thank offering unleavened cakes mixed with oil, unleavened wafers spread with oil, and cakes of fine flour well mixed with oil.

Matthew Henry's Commentary on Leviticus 7:12

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.