The Index Librorum Prohibitorum was a list of publications deemed heretical, anti-clerical or lascivious, and therefore banned by the Catholic Church. The Church has earlier examples of forming a formal prohibition of works including the Muratorian Canon around AD 170, which set to establish what was acceptable to have in the New Testament and what was heretical. The 9th century also witnessed the creation of what is considered to be the first index called the Decretem Glasianum but was never officially authorized. Much later, a first version (the Pauline Index) was promulgated by Pope Paul IV in 1559, which Paul F. Grendler believed marked "the turning-point for the freedom of enquiry in the Catholic world", and which lasted less than a year, being then replaced by what was called the Tridentine Index (because it was authorized at the Council of Trent), which relaxed aspects of the Pauline Index that had been criticized and had prevented its acceptance.