One of the many deep, theological, biblical, and practical differences between Roman Catholic churches and Reformed churches is the understanding of the sacrament of Holy Communion. Rome teaches that in the Eucharist, the bread and wine become Christ’s actual body and blood which are then offered on the altar as a sacrifice. “The Eucharist is the memorial of Christ’s Passover, the making present and the sacramental offering of his unique sacrifice. …In this divine sacrifice which is celebrated in the Mass, the same Christ who offered himself once in a bloody manner on the altar of the cross is contained and is offered in an unbloody manner” (Catechism of the Catholic Church, Part 2, Article 3, various sections).
The entire discussion would fill a book, but suffice it to say here that the confessional Reformed response completely resists the ideas of “sacrifice” and “altar” when it comes to the bread and wine of Holy Communion. The Heidelberg Catechism shows how Rome’s understanding of the Lord’s Supper throws a dark fog over the gospel:
“…the Mass teaches that the living and the dead do not have their sins forgiven through the suffering of Christ unless Christ is still offered for them daily by the priests. It also teaches that Christ is bodily present in the form of bread and wine where Christ is therefore to be worshiped. Thus the Mass is basically nothing but a denial of the one sacrifice and suffering of Jesus Christ and a condemnable idolatry” (Q/A 80).
I like how Herman Bavinck talks about the altar, the sacrifice, and the Lord’s Supper based on Hebrews. (The quote at the end of Bavinck’s paragraph is from Calvin’s Institutes.)
“The difference between the worship of the Lord and that of the New Testament consists…in the fact that temple and altar, priest and sacrifice, are no longer in earth but in heaven. The Jerusalem that is above is the mother of us all (Gal. 4.26). This is where Christ, our eternal high priest, has entered on our behalf (Heb. 6.20) after having by one sacrifice accomplished an external redemption (9.12), to appear before the face of God for us (9.24). There Christians have their sanctuary, into which they enter with boldness through the blood of Jesus (4.16, 10.19, 12.22). Here on earth we merely meet among ourselves, a meeting in which there is no room for sacrifice (10.25). The only altar Christians have is the cross on which Christ brought his sacrifice (13.10; cf 7.27, 10.10). From that altar, that is, from the sacrifice brought on it, they eat when by faith they have communion with Christ and his benefits. Believers have to bring no sacrifice other than the sacrifice of praise, the fruit of lips that praise his name (13.15). The Lord’s Supper is a sacrificial meal, a meal of believers with Christ on the basis of his sacrifice and therefore one that must be served on a table, not an altar. ‘This is indeed very certain: that the cross of Christ is overthrown, as soon as the altar is set up.”
Well said. Based on that summary of Hebrews, I also agree with the Westminster Confession of Faith (29.2) which says that the sacrament of the Lord’s Supper is not an offering or real sacrifice for the forgiveness of sins. Rather it is a commemoration of Christ’s sacrifice he offered, once for all, on the cross as well as a spiritual act of thanksgiving and praise. “The Popish sacrifice of the mass is most abominably injurious to Christ’s one, only sacrifice, the alone propitiation for all the sins of his elect.”
The above quote by Bavinck is found in volume four of Reformed Dogmatics (p. 566).