Liguori

Today is the feast of St. Alphonsus Maria de' Liguori, Doctor of the Church, founder of the Redemptorists, patron saint of confessors and moral theologians. From his work on the Mass:

We must also know that the Old Law exacted five conditions in regard to the victims which were to be offered to God so as to be agreeable to him; namely, sanctification, oblation, immolation, consumption, and participation.

1. The victim had to be sanctified, or consecrated to God, so that there might not be offered to him anything that was not holy or unworthy of his majesty. Hence, the animal destined for sacrifice had to be without stain, without defect; it was not to be blind, lame, weak, nor deformed, according to what was prescribed in the Book of Deuteronomy....

2. The victim had to be offered to God; this was done by certain words that the Lord himself had prescribed.

3. It had to be immolated, or put to death; but this immolation was not always brought about by death, properly so called; for the sacrifice of the loaves of proposition, or show-bread, was accomplished, for example, without using iron or fire, but only by means of the natural heat of those who ate of them.

4. The victim had to be consumed. This was done by fire. The sacrifice in which the victim was entirely consumed by fire was called holocaust. The victim was thus entirely annihilated in order to indicate by this destruction the unlimited power that God has over all his creatures, and that he created them out of nothing, so he can reduce them to the nothingness from which they came. In fact, the principal end of the sacrifice is to acknowledge God as a sovereign being, so superior to all things that everything before him is purely nothing; for all things are nothing in the presence of him who possesses all things in himself....

5. All the people, together with the priest, had to be partakers of the victim. Hence, in the sacrifices, excepting the holocaust, the victim was divided into three parts, one part of which was destined for the priest, one for the people, and one for the fire. This last part was regarded as belonging to God, who by this means communicated in some manner with those who were partakers of the victim.

These five conditions are found reunited in the sacrifice of the Paschal Lamb.