The Ascension of Isaiah is an ancient apocalyptic work that early Christians knew well. It was written under a false name and claimed to be by the prophet Isaiah. It is also known as the Martyrdom of Isaiah, the Testament of Hezekiah, or the Vision of Isaiah. The work was rediscovered in 1819 with the publication of an Ethiopic version of part of the text. The complete Ethiopic version is the only complete version in existence. The partial Latin text published in 1832 had actually been published over 300 years earlier. Slavonic and Coptic versions also exist. All of these versions come from two Greek originals that date to about the third through sixth centuries AD.
Scholars are unsure if the original work was written as one book or as several separate writings that were later joined together. It is also uncertain whether the first author was Jewish or Christian. The final form of the text could be from the late second century AD. Early church writers such as Ambrose, Jerome, Origen, Tertullian, and possibly Justin Martyr knew about it.
The book is made up of three main parts:
The Martyrdom of Isaiah. This material includes prophetic statements, such as the prophet predicting his own execution by King Manasseh of Judah. The document addresses the king's severe departure from the faith. Possessed by Satan and following Beliar, the king leads his people into many sins. The city is compared to “Sodom,” and its leaders are called “Gomorrah,” symbolizing wickedness. Written in the style of a Jewish midrash (a devotional sermon that explains Scripture), this section focuses on Isaiah’s strong faith and his refusal to deny God. It ends with his martyrdom, when he is killed by being “sawn in two,” a story known to many of the church fathers (see Hebrews 11:37).
The Testament of Hezekiah. Here Isaiah tells King Hezekiah a vision about the coming of “the Beloved,” a title for the Messiah (God’s chosen one). The vision includes the Messiah's birth, life, death, resurrection, and ascension. After this, it speaks about the early history of the church and the departure from faith that takes place before the Lord's second coming. The antichrist is revealed to be Beliar or Satan, who has taken human form and kills his mother. Many scholars think this description points to the Roman emperor Nero, who murdered his mother, Agrippina.
This section draws ideas from the biblical books of Daniel and Revelation. It also shows influence from Gnosticism, a religious movement that combined Christian belief with Greek philosophy. Gnostics claimed that people could be saved through secret spiritual knowledge rather than through faith in Christ.
The vision ends with the Beloved's victory, two resurrections, and the final judgment, similar to the ending of the New Testament book of Revelation.
The Vision of Isaiah. This part is closely related to the previous vision but shows even stronger Gnostic influence. Isaiah travels through the seven heavens and reaches the home of the Trinity (Father, Son, and Holy Spirit). There he sees the mysteries of Christ and the heavenly world. Because of this vision, King Manasseh orders his death.
Some of the ideas in this version of the story are similar to what Gnostic teachers, such as Cerinthus, taught. They said Jesus and the Christ were two different beings and that Christ entered Jesus at baptism and left before his death. This false teaching appears in parts of the text.
The Ascension of Isaiah shows how many different religious ideas were competing for authority in the early centuries of the Christian faith.