Index Librorum Prohibitorum
The Index Librorum Prohibitorum, or "Index of Forbidden Books," was a catalog maintained by the Roman Catholic Church that listed publications deemed inappropriate for lay Catholics. Established during the Council of Trent in 1559, the Index served as a means of censorship, reflecting the church's desire to protect its followers from materials considered heretical or morally corrupt. Over its nearly four-century span until its discontinuation in 1966, the Index contained more than four thousand titles, encompassing theological, philosophical, scientific, and literary works.
The church's censorship efforts dated back to its early centuries, including various councils and papal decrees that condemned specific writings. The Index outlined rules against reading, owning, or disseminating the listed works, and noncompliance was regarded as a grave sin. While the Index sought to balance doctrinal purity with the freedom of inquiry, it ultimately represented a significant manifestation of the church's authority over intellectual discourse. After the Second Vatican Council, the Index was recognized as a historical document, but the church retained the right to censor works that contradicted its teachings.
Index Librorum Prohibitorum
- TYPE OF WORK: Catalog
- PERIOD ENFORCED: 1559-1966
- PUBLISHERS: The Vatican and other agencies of the church
- SUBJECT MATTER: Catalogs of books banned by the Roman Catholic Church
- SIGNIFICANCE: These catalogs of “forbidden books” were historically the most significant manifestations of official Roman Catholic censorship
Instances of Roman Catholic book censorship can be traced back to the church’s early first centuries. From the fourth century CE into the sixteenth century, church leaders periodically compiled lists of banned books; however, the church did not establish its official index of prohibited books, the Index Librorum Prohibitorum, until the Council of Trent in 1559. The Vatican and other Roman Catholic authorities issued many variations of this list until 1966 when it was discontinued. By then, the Index had reached more than four thousand titles.
These indexes were alphabetical listings of works that lay Catholics were forbidden to read without permission from church authorities. Their purpose was not to be systematic listings of all possible banned books but cumulative listings of individual church decisions. During the Reformation, the church took extensive measures to condemn Martin Luther’s writings and other works considered heretical. Bishops, provincial councils, and universities issued catalogs of forbidden books, whose civil authorities often enforced bannings in consultation with the clergy. For example, England’s King Henry VIII had a strict policy of prohibiting books that he deemed objectionable. To preserve a theological and moral code among its followers, the church took measures to protect its members from being exposed to material it considered heretical. The Index contained general guidelines for restricted reading; most books it listed were theological, philosophical, and scientific treatises and literary works.
Historical Perspective
According to its canonical law, the Roman Catholic church has the right of censorship by virtue of natural law and its supernatural mission. Competent ecclesiastical authorities have a responsibility to protect membership in matters of religion and morals, as the church is seen as an effective instrument for the salvation of the human race. The church’s concern for striking a balance between freedom of inquiry and purity of doctrine is documented in the Index Librorum Prohibitorum. Early allusions to censorship can be traced back to apostolic times. Acts of the Apostles and Paul’s Epistle to Titus contain references to writings that Christians should not read. The church’s policy on book censorship began around 170 CE with the Muratorian Canon. In 325 CE, the First Council of Nicaea condemned the Greek ecclesiastic Arius’ book, Thalia. The first formal listing of forbidden books was made by Pope Innocent I in 405. Ninety-three years later, a council in Rome published an index of forbidden books known as the Gelasian Decree. It included lists of authentic scriptural books, recommended readings, and heretical books. Between the fifth and sixteenth centuries, there were many specific laws against reading certain books that were considered heretical by the church.
Examples of book censorship through that millennium included the Three Chapters, which was condemned in 548 by Pope Vigilius. Forty-one years later, the Council of Toledo forbade books on Arianism. The writings of Monothelites were condemned in 649 by Pope Martin I. The works of Adalbertus and Clement were forbidden in 745 by Pope Zacharias. In 869, Pope Adrian II burned the books written by Photius. Also condemned were works by Abbot Joachim in the thirteenth century, Peter Jean Olivi in the fourteenth century, and John Wyclif and Jan Hus in the fifteenth century. In 1469, Pope Innocent III decreed that all books would be submitted to local bishops for examination before being issued for general reading—an edict repeated by Pope Leo X in 1515. Book bannings became more frequent after the Council of Trent in 1559. Revised indexes were issued through the succeeding centuries, the last in 1948. Eighteen years later, in 1966, the church declared the Index to be a historical document that would not be reissued again.
Rules of the Index
It was unlawful for Catholics to read, translate, own, or print a forbidden book. General decrees prohibited books defending heresies; books that were considered obscene; books on spiritualism, sorcery, or superstitions; books defending divorce, suicide, or socialism; and newspapers and magazines that regularly attacked religion, morality, or Roman Catholicism. Certain types of publications had to be approved by bishops. Publications requiring their formal approval, or imprimatur, included theological works; books and pamphlets on devotion, religious instruction, and piety; and books, pamphlets, and leaflets on apparitions, visions, or miracles. Noncompliance with the rules was considered a mortal sin, but exemptions were granted to those engaged in theological, historical, or philosophical studies. Permission in writing was required.
The Index Expurgatorius, which is often confused with the Index Librorum Prohibitorum, was a list of passages deleted from certain books, which could be read only after they were expurgated by church officials.
The Council of Trent
This council, which met in 1545-1563, codified church regulations on book censorship. At one of its sessions, the church leaders authorized the use of the Vulgate version of the Bible for sermons and public discussions and ruled that no books on religion could be issued without prior approval of the church. In 1557, Pope Paul IV asked the Congregation of the Inquisition to compile a list of forbidden books published in 1559. This became the first official Index Librorum Prohibitorum. The Council of Trent undertook to revise the Index because of dissatisfaction among Catholic leaders. The project was too complex to be finished by the council, however, and was left to be completed by the Holy See.
In 1564, after the Council of Trent, Pope Paul IV introduced his Tridentine Index, which included a list of forbidden books and ten rules regulating censorship and reading of future books. Its first nine rules concerned works that were to be automatically forbidden because they were thought to be heretical or against church teachings. The last rule required examination and censorship of works prior to authorization of publication. An amended Index was ordered by Pope Pius V. Two editions of the Index were ordered by Popes Clement III and Alexander VII in 1664. Jansenistic works were added to the list. In 1753, Pope Benedict XIV issued a bull, Sollicita ac Provida, which remained the basic church document on forbidden works until 1897, with new titles being added each year.
The Modern Index
During the First Vatican Council, church fathers asked for a revision of the Index. However, the council adjourned before the issue could be resolved. In 1897, Pope Leo XIII gave the church a new Index, along with new regulations; his revised Index Librorum Prohibitorum was officially published in 1900. Little change took place under the general legislation of the Code of Canon Law (1917), which described the general classes of restricted writings: editions of the Bible lacking ecclesiastic license (Imprimatur) to be printed; books on Catholicism lacking an Imprimatur; books attacking religion, morals, Catholic dogma, divine worship, church discipline, bishops, or the clerical or religious state; books that defend divorce, suicide, heresy, schism, or superstitious practices; and books that are deliberately obscene. Popes, through the Holy Office (Sacrum Officium) have exercised the right to condemn books considered offensive to the church. In 1948, the last edition of Index Librorum Prohibitorum was issued.
During the Second Vatican Council in the early 1960s, Pope John XXIII proposed a revision of all church laws, including the Index, which was declared primarily a historical document in 1966. The new regulations emphasized the positive value of books. Bishops became responsible for cooperating with authors and publishers to ensure that the church remained the custodian of divine revelation and the interpreter of the teachings of Christ. Restrictions on reading became more liberal; however, permission was still required for some publications for purposes of accuracy; for example, portions of the Latin Bible, vernacular translations of the Bible, catechisms, and Catholic decrees. Members of religious communities still needed special authorization to publish commercial books on morals and religion. Although many changes have taken place regarding the Index Librorum Prohibitorum to keep it in tune with modern society, the church reserved the right to censor materials that are deliberately against Catholic theology, dogma, or moral teachings. The main body of church regulation was detailed in codes that are exhortative rather than obligatory. Individual authors and publishers were asked to exercise proper moral judgment over the works they published.
Bibliography
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