Transubstantiation is, according to the teaching of the Catholic Church, "the change of the whole substance of bread into the substance of the Body of Christ and of the whole substance of wine into the substance of the Blood of Christ". This change is brought about in the eucharistic prayer through the efficacy of the word of Christ and by the action of the Holy Spirit. However, "the outward characteristics of bread and wine, that is the 'eucharistic species', remain unaltered". In this teaching, the notions of "substance" and "transubstantiation" are not linked with any particular theory of metaphysics.
Transubstantiation – the real presence of Jesus in the Eucharistic Adoration at Saint Thomas Aquinas Cathedral in Reno, Nevada
A 3rd-century fresco in the Catacomb of Callixtus, interpreted by the archaeologist Joseph Wilpert as showing on the left Jesus multiplying bread and fish, a symbol of the Eucharistic consecration, and on the right a representation of the deceased, who through participation in the Eucharist has obtained eternal happiness
The Last Supper (upper image) and preparatory washing of feet (lower image) in a 1220 manuscript in the Baden State Library, Karlsruhe, Germany
Title page of Martin Luther's De Captivitate Babylonica Ecclesiae
The Catholic Church, also known as the Roman Catholic Church, is the largest Christian church, with 1.39 billion baptized Catholics worldwide as of 2022. It is among the world's oldest and largest international institutions, and has played a prominent role in the history and development of Western civilization. The church consists of 24 sui iuris churches, including the Latin Church and 23 Eastern Catholic Churches, which comprise almost 3,500 dioceses and eparchies located around the world. The pope, who is the bishop of Rome, is the chief pastor of the church. The Diocese of Rome, known as the Holy See, is the central governing authority of the church. The administrative body of the Holy See, the Roman Curia, has its principal offices in Vatican City, a small independent city-state and enclave within the Italian capital city of Rome, of which the pope is head of state.
St. Peter's Basilica in Vatican City, the largest Catholic church building in the world
The first use of the term "Catholic Church", meaning "universal church", was by the church father Saint Ignatius of Antioch in his Letter to the Smyrnaeans in c. 110 AD. Ignatius of Antioch also is credited with the first recorded use of the term Christianity ten years earlier, in c. 100 AD. He died in Rome, with his relics located in San Clemente al Laterano.
A c. 1481–1482 fresco by Pietro Perugino in the Sistine Chapel showing Jesus giving the keys of heaven to Saint Peter
The Last Supper, a late 1490s mural painting by Leonardo da Vinci, depicting the last supper of Jesus and his twelve apostles on the eve of his crucifixion. Most of Jesus' apostles are buried in Rome, including Saint Peter.