As one of the most referenced books in the Old Testament, the book of Isaiah holds a place of high significance for the Christian faith. Recounting the life and teachings of the prophet Isaiah who lived in the Kingdom of Judah during the 8th century BCE, it is a call to turn back to God and to put our faith in Him. Furthermore, the text sets the stage for Jesus Christ as the fulfillment of the coming messiah that Isaiah predicted.
The question "who wrote the book of Isaiah" or "who wrote Isaiah" is a complex one. We’ll explore some of the most prominent theories held by scholars as to who exactly wrote this Biblical book.
Before we turn our attention to the question of isaiah's authorship, let us first set the stage for the book of Isaiah.
When the book opens, Isaiah, a prophet of the southern kingdom, has been called by God to share His message with the people in 740 BCE. The year is significant for being the year that King Uzziah died. The late Eighth century was a critical period in the history of the southern kingdom of Judah. Uzziah was known as one of the best kings Judah had. His rule marked a time of great prosperity for the kingdom. But as prosperity boomed, the divide between the rich and poor in the kingdom grew wider, and all the while the threat of invasion from Assyria was mounting.
When King Uzziah contracted leprosy, the political situation grew even more dire, and Uzziah was forced to give over the throne of the nation of Judah to his son, Jotham. Unlike his father, Jotham was a weak and vacillating person and was unable to inspire confidence in his people. This is the political situation in which Isaiah's prophetic work begins.
Although the book primarily centers around the messages and teachings that God gave to the people of Israel through the prophet Isaiah ben Amoz, the scholarly consensus is that the book of Isaiah was not written by its namesake prophet singlehandedly. The book covers an expansive period of time--compiled over a period of approximately two centuries, which seems to point to it being a composition of several major prophets or writers active during this period of Israel’s history. One of the major ways scholars discuss the authorship of Isaiah is by dividing the text into three distinct sections: Proto-Isaiah (chapters 1-39), Deutero-Isaiah (40-55), and Trito-Isaiah (56-66). The three sections are sometimes referred to as simply First Isaiah, Second Isaiah, and Third Isaiah respectively. (This three-part division is different from the common two-part way which focuses on literary characteristics of the book. To learn more, see “What is the Book of Isaiah About?”)
Proto or First Isaiah is the section of the text that Biblical scholars are most confident in attributing to the historical Jewish prophet Isaiah. This section is believed to have been written during the Eighth Century BCE, prior to the Assyrian invasion and well before the Babylonian exile and captivity. Since the assumed time of composition corresponds with when the historical Isaiah was active, it makes sense that this would be the section he helped to author. The First Isaiah looks ahead and warns of a coming judgment against the people of Israel and Judah by way of foreign invasion.
Most scholars agree that the second Isaiah section, Deutero-Isaiah, was likely written by an anonymous author (or authors) in the Sixth century BCE when the Jewish people were in exile. Since this is a time jump of approximately 150 years, we can assume that Isaiah ben Amoz did not have a hand in writing this section, though scholars do not have a specific figure they believe to be the author. In Deutero-Isaiah, the city of Jerusalem has already been destroyed and the people are living in captivity. In contrast to Proto-Isaiah with its word of condemnation and coming judgment, Deutro-Isaiah speaks far more on the coming restoration and the promised messiah. This again points to a later composition date; exile and judgment have come down of the people, just as God warned. In the aftermath, the messages God sent to His prophet center around His plans to heal and uplift His people.
Finally, we come to Third Isaiah, which jumps in time yet again. It references the construction of the second temple; this seems to imply that this section was written after the people returned from the Babylonian exile. The author of this book is also unknown and typically assumed to have been written anonymously in the post-exilic period. Trito-Isaiah is sometimes referred to as a compilation--a section made up of writings from other prophets and Jewish sages during the early days of rebuilding after the exile. This section outlines the need for a redeemer and tells of what the coming restoration (or Messianic Age) will be like.
While the notion of multiple authorship for the book of Isaiah might be surprising or unsettling for some, it needn't be. Critical scholars have frequently remarked upon the book's essential unity despite being the work of multiple authors. The cohesion of the entire book reminds us that regardless of its human origins, Isaiah is the inspired Word of God. Whether spoken through one person or several, the purpose of the text is to convey God's wisdom and teaching for His people, particularly in times of tumult and struggle.
Through the book of Isaiah, God speaks out against corrupt leaders and for the disadvantaged; He offers a vision of hope and comfort in humanity's darkest hour. Isaiah constitutes a call to turn back to God and to put our faith in Him, and it sets the stage for the coming of Jesus Christ as the fulfillment of the coming messiah that the prophet(s) predicted.
To learn more about the book of Isaiah and the wisdom of God’s Word found in the hebrew Bible, take a look at the complete collection of beautiful Bibles from Alabaster.