APOCALYPSE (Gr. ἀποκάλυψις, unveiling), or Revelation of St. John, the name of the last book of the New Testament. The church at an early period appears to have ascribed the authorship of the book to John the evangelist. Papias and Melito of Sardis, according to the testimony of Eusebius, regarded the Apocalypse as inspired. Justin Martyr and Irenæus expressly quote the Apocalypse as the work of the apostle John; and the third council at Carthage, in 397, admitted it into its list of canonical books. On the other hand, Dionysius, bishop of Alexandria, testifies that some church writers before him repudiated the Apocalypse as a forgery of Cerinthus; and he himself undertakes to prove that it was not the work of the apostle John, but of some other John who lived in Asia. That this opinion was shared by other prominent men of the church may be inferred from the fact that the Apocalypse is absent from the ancient Peshito version. Jerome moreover states that the Greek church felt with regard to the Apocalypse a doubt similar to that entertained by the Latins with regard to the Epistle to the Hebrews. The rejection of the canonical and apostolical character of the book was chiefly prompted by opposition to chiliasm; and when the interest in the chiliastic controversies declined, the church generally recognized the Apocalypse as a work of the apostle John. In modern times the question of the apostolic origin of the book was revived by Semler, and many of the prominent exegetical writers of the Protestant churches (in particular De Wette, Ewald, Lücke, and Baur) undertook to prove that the Apocalypse and the Gospel of John could not possibly have been written by the same author. While, however, most of these writers deny that it was written by the apostle John, Baur, Hilgenfeld, and other critics of the Tübingen school, ascribe the Apocalypse to him, but not the fourth Gospel. Among those who have recently undertaken to prove that neither the fourth Gospel nor the Apocalypse was written by St. John, Th. Keim (Geschichte Jesu von Nazara, vol. i., 1867) and Scholten (De Apostel Johannes in Klein-Azie, Leyden, 1871) are the most prominent. The Johannean origin of both the Apocalypse and the fourth Gospel was, on the other hand, vindicated against the critical schools by Hengstenberg, Hase, Godet, and in particular by Niermeyer (Verhandeling over de Echtheid der Johanneische Schriften, the Hague, 1852). — No book of the New Testament has received so many different interpretations. Two principal classes of expositors may be distinguished, the historical or continuous and the preterist. According to the opinion of the former, which is shared by nearly the entire ancient church, the Apocalypse is a progressive representation of the entire history of the church and the world. Sir Isaac Newton, Bengel, E. B. Elliott, Wordsworth, Hengstenberg, Ebrard, and Alford are prominent representatives of this class. Writers of this school have found in the Apocalyptic visions prophetic references to nearly every great event of the Christian era, such as the migration of nations, the reformation, the pope, the French revolution, and Napoleon; and the calculations of the millennium have led to varying results, and in some instances even to the establishment of particular sects. The date of the Apocalypse is given by these writers as A. D. 95-97. The preterist mode of interpretation, according to which the Apocalypse has been almost or quite fulfilled in the time which has passed since it was written, and refers principally to the triumph of Christianity over Judaism and paganism, found able advocates in Grotius, Bossuet, and Calmet, and since Herder and Eichhorn has become the exclusive interpretation of all the liberal Protestant schools of theologians. Among the recent champions of this school, Ewald, Lücke, Bleek, Stuart, Lee, and Maurice are best known. According to their view, the seven heads are seven emperors. As Galba was accounted as the sixth of the emperors, the book is supposed to have been written during his reign (in 68). The fifth, who will return as the eighth, is Nero, who at that time was believed not to be dead, but to have retired to Parthia, whence he would return. In the symbolical number 666 these writers commonly find the words “Neron Kaisar,” written in Hebrew letters. Some writers, chiefly English, believe that, with the exception of the first three chapters, the book refers wholly or principally to events which are yet to come. Swedenborg regards the Apocalypse as a peculiar revelation of divine truth, the book of all books which is least encumbered by literal references to mundane things, and most remarkable for the completeness with which it contains the heavenly word.