While discussions of the Holy Mass by the "Liturgical Movement" [01; 02; 03; 04] generally is about a Christianized Synagogue Service and the Last Supper with a Nucleus of the Euchrist's Proper as the origin of the Holy Mass without referring to the essential link to the Old Testament Temple Cult. These discussions are more about (alleged) historical developments regarding the form than about the essence of the Holy Mass. Furthermore, by misunderstanding the true distinction between the natural and supernatural orders, they went so far as to judge the correctness of development by "Organic Growth". All this is then based on an amateurish archeology, in which they set aside the Doctrine and Practices, which have been preserved by the Holy Spirit throughout the ages through the "Organic Growth" under the refutation of heresies and the adoration of Christ in all aspects of how He has fulfilled the Law. It is this pride that resulted in their blindness to see the essence that Christ was born to fulfill the Law and how that is connected to the fulfillment of the Temple cult of the Old Testament. Namely that Christ fulfilled the Law that regulates the Jewish Temple cult in its entirety, which also means that the Holy Mass is the fulfillment of the Temple cult of the Old Testament: the Eucharist is a Sacrifice.
Without claiming to be complete an overview of the fulfilment is given here in its main points concerning the last week of Passion.
The fulfilment of the Law, certainly, did not start with Christ hanging on the Cross, Christ standing before the Sanhedrin or Christ instituting the Eucharist at the Last Supper or something like that. Apparently, Christ's fulfillment of the Law refers to His entire earthly life, from Conception to His Death on the Cross. He was born as the "Innocent Lamb of God" in the Stable of David. This was the stable from which the lambs came to be sacrificed in the Temple. So, also Christ, as the "Innocent Lamb of God", was born in this Stable to be sacrificed in the Temple. However Christ, the "Innocent Lamb of God" was led out of the City of Jerusalem as a "Scapegoat" where He offered Himself on the Cross for our sins and then rose from the death because He was without sin. Thus it is Christ, Priest in the order of Melchisedech, who ultimately fulfilled the Law by offering His Body for our sins on Golgotha (Lk 24:44-49). The Holy Mass can therefore only be associated with this ultimate culmination of the fulfillment of the Old Testament Temple Cult through the two related Temple Feasts of "Passover" and "Yom Kippur".
This fulfillment is therefore connected to the books of the Old Testament which proclaimed the Law. It therefore follows Exodus and Leviticus among others in its context of the "Exodus from Egypt, the land of slavery", which had a paradigm shift by its fulfillment to the "Exodus from the land of the slavery of sin".
Therefore, this process of fulfillment follows the Law as given in the Temple cult of the Old Testament. A rough outline of the fulfillment is given here with reference to the main points in the last week, the week of Passion, as follows:
Thus "a holy priesthood" who "offer spiritual sacrifices acceptable to God through Jesus Christ" (I Peter 2:5) during which the ordained priests "in Person of the High Priest, Christ" offers the Passover Lamb and then "in Person of the High Priest, Christ" eats and drink the Body and Blood of Christ,the Passover Lamb, as Sacrificial (Spiritual) Meal, after which the faithful are invited as the "Holy Priesthood" to join the Sacrifice by eating the Body of Christ. This is the one, true and eternal Sacrifice of the Eternal Passover Lamb, who is unblemished and appointed to be a "Scapegoat" He is bearing our sins. In this way Christ used the context of the Passover as a Memory of the "Exodus from Egypt, the land of slavery" through the associated Feast of "Yom Kippur" for a paradigm shift into a commemoration of Christ as a Memory of the "Exodus out of the land of slavery to sin" of which He is the door to Heaven.
While the institution of the Eucharist by Christ at the Last Supper was on the Thursday evening. This Last Supper could therefore neither be a Sabbath meal, as suggested by the new Offertory prayers of the 1969 Reform, nor the Sacrificial Passover Meal of Pesach. While the Old Testament day is from sunset to sunset Thursday evening was one day too early for it. Rather, it was the first meal of the 14th day of the first month when the 7-day Feast of the Unleavened Bread began. Whereas the Unleavened Bread signifies being unblemished (I Cor. 5:7, I John 3:5, Hebr. 7:26) in contrast to the leaven bread that stands as the common symbol for Sin (Amos 4:5, Hosea 7:4, Lk 12:1, Matt. 16:6-12, Gal. 5:9, I Cor. 5:6-8). So, the Last Supper was the first Passover Meal at which the symbolic Unleavened Bread was eaten in the evening before the Sacrificial Passover Meal. It was from this meal that Christ used the symbolic Unleavened Bread and Wine for a paradigm shift into His innocent and unblemished Body and Blood. That is why Christ had to institute the Eucharist at the Last Supper by commanding the apostles, "Do this in remembrance of me". With "Do this ..." He did not command them to repeat the Last Supper, but to repeat His Acts in union with and in commemoration of His Sacrifice on the cross as the ultimate climax of the fulfilment of the Law: "He took the Bread and blessed it", "He took the Cup and blessed it" (= Offertory: taking Bread and Wine from profane use to prepare them by offering it our Lord for sacred use), then "He consecrated both, Bread and Wine" (= Consecration) with "the Remembrance" (= Anamnesis), after which "He broke the consecrated bread" (= Fraction) and finally "he gave to eat the consecrated bread and wine, his flesh and blood" (= Communion as the Sacrificial/Spiritual Meal). While ". . . in remembrance of me" can only mean the remembrance of Christ's fulfillment of the law in all its facets, how He has redeemed us.
The institution of the Eucharist, therefore, does not refer to the Last Supper or the Synagogue Service, but as the fulfilment of the Old Testament Temple Cult the H. Mass is in its entirity the New Testament Temple Cult focussed on the Sacrifice of our Lord as the innocent Lamb of God bearing as Scapegoat our sins. As such, the Eucharist is the same true and eternal Sacrifice for our sins in which Christ ultimately fulfilled the entire Old Testament Temple Cult. Mystically, the Eucharist at the Last Supper, preceding the Crucifixion, as well as all those taking place since then at each H. Mass by Christ in His "Mystical Body" is one and the same as the physical Sacrifice at Golgotha, It is Christ, the Eternal High Priest, who offers and sacrifices Himself on the cross for our sins.