Updated: May 28
By Luke Lancaster
Scripture shows that sacred actions (sacraments) were done in the early Christian communities, such as baptism and the Lord’s Supper. The medieval theologian, St. Thomas Aquinas, expounds upon these sacraments in his massive work, Summa Theologiae (ST). In the third part of the ST, in question 62, Aquinas gives the objection which the now common Protestant belief is - that the sacraments are simply symbols.
Is the sacrament of baptism just a symbol of our new life in Christ? Or does God work through the sacrament itself and give grace? Aquinas believes that it would be foolish to claim that the sacrament would only model the grace, but not also give it. For the sacrament is physically applied to and interacts with the recipient, so the most logical response would be that the sacrament is an instrument of God in causing grace.
The fact that the sacrament is involved in such a way is called, ex opere operato, that is, from the very rite itself. Scripture and the Magisterium teach this about the sacraments as well, that they truly are doing something, as opposed to doing nothing. So to answer the objection that Aquinas raises, the sacraments cause grace because the sacrament physically models the grace that is received by the believer, and because the Scriptures and the Magisterium teach it.
Aquinas explains what is meant by the sacraments causing grace in his theory called, “efficient causality.” It says that both God and the sacrament cause grace in the individual, just as a guitarist and a guitar work together to create music. The guitarist is the principle agent that decides to make the music, and the guitar is the instrument that he uses to accomplish that goal. The guitar is vital to make music, but music can only be made under the influence of the guitarist. So efficient causality means that God and the sacraments both cause grace and are united in their purpose to do so in the believer.
Sacred Scripture attests to the fact that the sacraments are signs of grace, but it also implies that they cause the grace signified. In Romans 6:3-5, St. Paul speaks about what happens during the sacrament of baptism,
“Do you not know that all of us who have been baptized into Christ Jesus were baptized into his death? We were buried therefore with him by baptism into death, so that as Christ was raised from the dead by the glory of the Father, we too might walk in newness of life. For…we have been united with him in a death like his.”
When a believer gets a baptism of immersion, he is literally immersed in water which symbolizes his "drowning." St. Paul says that that death by drowning symbolizes our spiritually dying with Christ. Then when the believer rises from the water, St. Paul tells us that symbolizes rising to newness of life. All of this is not just symbolic, however, according to the text. For he then said that, “we have been united with him in a death like his.” It was not just symbolic, the baptism literally united the person to Christ’s death, so that his sins were washed away.
St. Paul had just said before that quotation that they had “died to sin,” meaning the sins were washed away (Rom. 6:2). The previous way of life which the believer had lived was changed, in a concrete way, through the sacrament. It symbolized what it did, and the believer then lived a brand new life. So St. Paul taught that the sacrament of baptism symbolized what it did, and therefore, caused grace to be conveyed to the recipient.
Jesus also taught that the sacraments themselves cause grace by doing what they signify, and that they truly and physically apply grace to the believer. Take Jesus’ action at the Last Supper, “He took bread, and when he had given thanks he broke it and gave it to them, saying, ‘This is my body which is given for you. Do this in remembrance of me’ (Lk. 22:19).” There is a sign of grace in this sacrament, and that is that it symbolizes man eating and receiving Christ’s divine life. That grace, however, is not just a sign of grace, but is actually applied when a believer receives the Eucharist. For Christ Himself said, “He who eats my flesh and drinks my blood abides in me, and I in him” (Jn. 6:56). So, according to the Scriptures, the sacraments do what they signify and cause grace.
The Magisterium of the Catholic Church has spoken about the sacraments causing grace numerous times. Pope Benedict XII in the fourteenth century condemned a group called the Armenians, who said that priests do nothing when forgiving sins in the sacrament of confession, but that only God forgave. The Pope said that the grace signified when the priest says, “I absolve you from all of your sins,” is not just a sign, but actually accomplishes the forgiveness of sins through the instrumentality of the priest, as efficient causality teaches. It is not just God, but God and the sacrament that cause the grace of forgiveness.
The Council of Trent (16th century) taught this as well, and against the Protestant reformers in particular. For when they said in one decree that those who deny that the grace symbolized in the sacraments actually confers the grace are anathema (excommunicated). The sacraments were not to be seen as rites that were empty and designed only for proclaiming faith in Christ. In another decree by the Council, it is stated that grace is not just received by the believer due to his faith, but instead, by participating in the sacraments themselves. The basic teaching of ex opere operato is seen here. The application of the sacrament truly participates with God in causing grace. So, the Magisterium believes that the sacraments cause grace to flow to the believer.
The truly Christian understanding of the sacraments is the one that is the most logical, and is in line with Scripture and the Magisterium. The only one that fits the criteria well is the efficient causality theory that Aquinas taught. Christ’s sacraments really are signs of grace as Scripture and the Magisterium have shown, but that is not all that they are. God and the sacraments both unite in causing grace to be received by the believer, as a guitarist and a guitar both unite in making music. To conclude, Dr. Roger Nutt says, “God has instituted the sacraments and works through them in such a way that he bestows the gift of grace,” and that really deepens, “his intimacy and presence with the faithful,” which, “hardly needs to be underscored."