Although when I repost things, I don't always intend to be taken as whole-heartedly agreeing with what is expressed therein, this strikes me as true:
Most Catholics of the time [the Sixteenth century] had a very exaggerated—exaggerated to the point of heresy—understanding of the “Sacrifice” of the Mass to which the reformers reacted strongly—too strongly by the standards of modern scholarship. In other words there were serious theological problems on both sides of this debate.
This is a précis of an article that resulted in a lot of different responses. The problem it initially identified was as follows:
The loss of the patristic heritage and its replacement with Scholastic Theology in the thirteenth and subsequent centuries created an appalling mystique to the Mass where it was claimed that Christ died anew and again day after day upon the altars. This stands in total contradiction to the scriptures where we are told that Christ died once for all (1 Peter 3:18; Romans 6:10; Hebrews 9:28). Each Mass was seen to be in its own right a propitiatory sacrifice and each priest an Aaronic priest who offered the victim to God on behalf of the people. The priest was not seen to be a sacramental sharer in the one priesthood of the One Priest, Christ, but like the priests of the Old Law a man who approached the sacrifice in virtue of his own priesthood.
The weakest sort of response is to dig around for puristic statements, from people such as Peter Lombard, when what is being adverted to above is the popular reception of disputable theological interpretations. This is what the reformers called "the Romish doctrine" (which is not at all the same as a dogma of catholic faith). If Lombard indeed said
... that which is offered and consecrated by the priest is called sacrifice and offering (oblatio), because it is the memory and representation of the true sacrifice and holy offering (immolatio) made on the altar of the Cross.
then that is all and very well good. But the problem for the reformers was that this was a far cry from what popular understandings were.
The stronger argument is formal: that this is proleptic. That is, the legal brief, that the consecration embodies, follows the old debate rule: tell them what you are going to say; say it; and then tell them what you said.
The sacrificial language of the Offertory, “receive… this immaculate victim … we offer Thee, Lord, the chalice … receive this offering” is an example of prolepsis, referring to the Sacrifice before what is actually sacrificed is present, namely, the Body and Blood of Christ. The literal Latin equivalent of prolepsis is “anticipation”, and it was dislike of this anticipation of the Sacrifice that ultimately led to the radical overhaul of the Offertory in the Novus Ordo.