To relate the history of the present while having an intense vision of the future, and at the same time to veil certain too recent realities with names taken from the past - this is all that is needed to turn a book into an enigma. Such is precisely the case of the work by which John the Evangelist, retired to the Island of Patmos, wished to put the finishing touches on the New Testament and the Bible by adding a picture of the approaching end of the world. In it Rome is masked by the name of Babylon and Nero by that of Nabuchodonosor.

The Apocalypse is the joy and the despair of the exegetes. Its symbolism is immense. It is so abundant that it is not excessive for the artists to come to the aid of the scholars. No other work has had such magnificent interpretations. The finest are unquestionably those of the illuminators of the Middle Ages, and in the first rank is a copy of the Commentary of Béatus realized in the eleventh century at the Abbaye de Saint-Sever, in the Landes.