Providentissimus Deus, "On the Study of Holy Scripture", was an encyclical letter issued by Pope Leo XIII on 18 November 1893. In it, he reviewed the history of Bible study from the time of the Church Fathers to the present, spoke against the errors of the Rationalists and "higher critics", and outlined principles of scripture study and guidelines for how scripture was to be taught in seminaries. He also addressed the issues of apparent contradictions between the Bible and physical science, or between one part of scripture and another, and how such apparent contradictions can be resolved. Context Providentissimus Deus followed earlier efforts on the part of Pope Leo to promote Catholic education. In 1878, he had encouraged the study of history and archaeology. The 1879 encyclical Aeterni Patris promoted the study of scholastic philosophy. In 1887 he encouraged the study of the natural sciences, and in 1891 opened the Vatican Observatory. Catholic studies in the seventeenth and eighteenth centuries avoided the use of critical methodology because of its rationalist tendencies. Frequent political revolutions, bitter opposition of liberalism to the church, and the expulsion of religious orders from France and Germany, made the church understandably suspicious of the new intellectual currents of the period. In 1892 Leo authorized the École Biblique in Jerusalem, the first Catholic school specifically dedicated to the critical study of the Bible. At the turn of the 20th century the official Catholic attitude to the study of Holy Scripture was one of cautious advance, and at the same time of a growing appreciation of what had promise for the future. With Providentissimus Deus, Pope Leo gave the first formal authorization for the use of critical methods in biblical scholarship. In 1902, Pope Leo XIII instituted the Pontifical Biblical Commission, which was to adapt Roman Catholic Biblical studies to modern scholarship and to protect Scripture against attacks. Content The encyclical contains both a polemic against rationalism, and a defense of divine authorship, inspiration, and inerrancy. Leo responded to two challenges to biblical authority, both of which arose during the 19th century. The historical-critical method of analyzing scripture questioned the reliability of the Bible. Leo acknowledged the possibility of errors introduced by scribes but forbade the interpretation that only some of scripture is inerrant, while other elements are fallible. Leo condemned that use that certain scholars made of new evidence, clearly referring to Alfred Firmin Loisy and Maurice