St. Thomas Aquinas is known for his “superhuman insight into the profoundest truths of our holy faith,” though “he himself tells us that he owed more to prayer, devotion to the Holy Eucharist, and to loving contemplation of the Crucified Savior than to all his studies.” He is renowned as perhaps the greatest theologian of the Church, especially for his “monumental” Summa Theologica, “a summary of the whole of philosophy and theology.”
He is also known as a “guardian of the doctrine of [the Church’s] central mystery, the Blessed Eucharist.” In his Summa, Aquinas offers us insight into various questions about the Eucharist, including why its institution was appropriate and how it was even foreshadowed in the Old Testament.
St. Thomas Aquinas: Life, Devotion to the Eucharist, and Miracles
Thomas Aquinas was born near Naples, Italy around 1224. He received his education in Monte Casino and Naples, and studied under the guidance of Alber the Great in Paris and Cologne for a total of seven years. After his father died in 1244, he became a Dominican friar, though this was against his family’s wishes, and later he became a priest. He was extremely intelligent and “taught with distinction at Paris, Rome, and Naples,” where “crowds of students flocked to hear him.” While he was at the Papal Court of Urban IV, “he composed the Mass and office for the feast of Corpus Christ” as well as five Eucharistic hymns in Latin.
Most astoundingly, though, while he was in Salerno writing a part of the Summa about Christ’s passion and Resurrection,  a miracle occurred in which Christ confirmed His approval of Thomas’ writings. As Thomas was kneeling in intense prayer before the altar, the crucifix in the chapel came to life, and Christ spoke to Him: “Well hast thou written of Me, Thomas. What reward do you ask?”—to which Thomas replied, “Thyself, O Lord: Ut te revelata cernens facie, Visu sim beatus tuae gloriae [For thy veil give me thy face, when Glory’s sun faith’s shades shall chase].” At this time, the other Dominican brothers even came into the chapel where he was praying, and found him miraculously levitating in the air.
By 1274, St. Thomas had become so renowned that Pope Gregory X asked him to attend the General Council of Lyons. While he was on his way there, however, he got sick and died at a Cistercian Monastery. As he was receiving last rites, his last words were filled with love for Christ in the Eucharist:
“I receive Thee,” he said, as he received the Eucharist, “redeeming Price of my soul. Out of love for Thee have I studied, watched through many nights, and exerted myself; Thee did I teach and preach. I never said aught against Thee. Nor do I persist stubbornly in my views. If I have ever expressed myself erroneously on this Sacrament, I submit to the judgment of the holy Roman Church, in the obedience to which I now part from this world.”
Aquinas’ Writing on the Eucharist: Established by Christ, Prefigured in the Paschal Lamb
Aquinas devoted part of his Summa Theologica specifically to questions about the Eucharist. First, he addressed whether it is a sacrament, and he noted that,“just as for the spiritual life there had to be Baptism, which is spiritual generation; and Confirmation, which is spiritual growth: so there needed to be the sacrament of the Eucharist, which is spiritual food.”Second, he addressed whether this is one sacrament or several, and whether it is necessary for salvation. Regarding the latter, he said that “the reality of the sacrament is the unity of the mystical body, without which there can be no salvation.”He describes the Eucharist as “the consummation of the spiritual life, and the end of all the sacraments.” However, he made the distinction that the desire to receive the sacrament is sufficient for salvation, even if one is unable to actually receive it. He also asked and answered whether the Eucharist is suitably called by various names.
Furthermore, the next question was whether the institution of this Sacrament was appropriate. He stated quite plainly that “this sacrament was instituted by Christ,” and that “this sacrament was appropriately instituted at the supper, when Christ conversed with His disciples for the last time.” He says that this was appropriate, “First of all, because of what is contained in the sacrament: for Christ is Himself contained in the Eucharist sacramentally.” Here he quotes Eusebius:
“Since He was going to withdraw His assumed body from their eyes, and bear it away to the stars, it was needful that on the day of the supper He should consecrate the sacrament of His body and blood for our sakes, in order that what was once offered up for our ransom should be fittingly worshiped in a mystery.”
Furthermore, Aquinas explains that:
“It was necessary accordingly that there should be at all times among men something to show forth our Lord’s Passion; the chief sacrament of which in the old Law was the Paschal Lamb. Hence the Apostle says (1 Corinthians 5:7): ‘Christ our Pasch is sacrificed.’ But its successor under the New Testament is the sacrament of the Eucharist, which is a remembrance of the Passion now past, just as the other was figurative of the Passion to come.”
Following this, St. Thomas elaborates in the next question how the Paschal Lamb was, in a certain sense, the chief figure (or foreshadowing symbol) of this sacrament. He explains how the Paschal Lamb that was sacrificed by the Israelites at the Passover prefigured (foreshadowed) the Eucharist in three ways:
First of all, the Paschal Lamb “was eaten with unleavened loaves, according to Exodus 12:8: ‘They shall eat flesh . . . and unleavened bread.’” This foreshowed the sacramental symbol, the unleavened bread of the Eucharist.
Second, the Paschal Lamb “was immolated [sacrificed] by the entire multitude of the children of Israel on the fourteenth day of the moon [the celebration of the Passover, when the Last Supper occurred]; and this was a figure of the Passion of Christ, Who is called the Lamb on account of His innocence.” Thus, this prefigured the reality behind the sacramental symbol—the body and blood of Christ.
Thirdly, “by the blood of the Paschal Lamb the children of Israel were preserved from the destroying Angel, and brought from the Egyptian captivity,” just as Christ’s blood, present in Eucharist, saves us from the slavery of sin and death; in this way, the effect of the sacrament was also prefigured. Therefore, Aquinas says, “in this respect the Paschal Lamb is the chief figure of this sacrament, because it represents it in every respect.”
If you’d like to see in more detail the support for the Eucharist from the New Testament, you can read my article, “Is the Eucharist Biblical?”
May God bless you and keep you!
Article image: Stained glass image depicting the crucifix speaking to Thomas Aquinas, Saint Patrick Church, Columbus, Ohio. https://en.wikipedia.org/wiki/File:Saint_Patrick_Church_(Columbus,_Ohio)_-_stained_glass,_St._Thomas_Aquinas,_detail.jpg
 John Laux, Church History (Charlotte, NC: TAN, 2012), 379.
 Ibid. 378.
 Bob and Penny Lord, “Jesus speaks to Saint Thomas Aquinas from the Crucifix,” Bob and Penny Lord, 2020. https://bobandpennylord.store/blogs/news/the-life-of-saint-thomas-aquinas.
 Bob and Penny Lord
 Thomas Aquinas, “Adoro te Devote.” Translated and adapted by Richard Crashaw, “Adoro te: Hymn in Adoration of the Blessed Sacrament.” Lieder.net. https://www.lieder.net/get_text.html?TextId=40992
 Laux 379.
 Bob and Penny Lord.
 Laux 379.
 Ibid. 378-379.
 Thomas Aquinas, “Question 73. The sacrament of the Eucharist,” Summa Theologica, Second and Revised Edition, 1920, trans. by Fathers of the English Dominican Province, Newadvent.org. https://www.newadvent.org/summa/4073.htm.