Who is the author of the Book of Isaiah?

Historical Setting and Context

The Book of Isaiah opens by identifying its writer in direct terms: “This is the vision concerning Judah and Jerusalem that Isaiah son of Amoz saw during the reigns of Uzziah, Jotham, Ahaz, and Hezekiah, kings of Judah” (Isaiah 1:1). This reference sets the historical stage in the latter half of the 8th century BC. During this period, the Assyrian Empire was expanding aggressively, and the Southern Kingdom of Judah faced both internal spiritual decline and external threats. It was in this environment that the prophet ministered, warning leaders, confronting idolatry, and foretelling future hope and redemption.

Isaiah’s ministry appears to extend from approximately 740 BC to at least 681 BC. The historical details throughout the text—such as events recorded under King Hezekiah (Isaiah 36–39)—fit well within the timeframe of the prophet’s activity. Assyrian records like the Sennacherib Prism corroborate the Assyrian invasion of Judah (including the siege of Jerusalem). Such archaeological findings confirm the political and military background frequently alluded to in the Book of Isaiah.

Traditional Single Authorship

For centuries, Jewish and Christian tradition has ascribed the entirety of Isaiah (chapters 1–66) to Isaiah, the son of Amoz. Early commentators, including those in the Qumran community (who preserved the Dead Sea Scrolls), treated Isaiah as a unified work. The Great Isaiah Scroll found at Qumran (1QIsᵃ), dated to around the second century BC, presents a complete copy of Isaiah that demonstrates remarkable textual consistency with later Masoretic manuscripts. This supports the longstanding view of one main prophet writing the book.

Additionally, the New Testament references to Isaiah often draw from multiple portions of the book but consistently identify all those sections as the work of the same prophet (see John 12:38–41, which cites Isaiah 53:1 and 6:10 together under the same prophetic name). Such unification in both ancient Jewish tradition and the New Testament indicates a well-established, continuous belief in Isaiah’s solitary authorship.

Evidence from the Text of Scripture

Internal evidence emphasizes the overarching prophetic voice that appears in the entire text. The recurring phrase “Thus says the LORD” (e.g., Isaiah 7:7, 8:5, 10:24, 43:1) maintains a cohesive tone, uniting each prophetic oracle under one divine message.

Jesus and the Gospel writers also cite Isaiah extensively. For example, in Luke 4:17–19, Jesus reads from Isaiah 61, then attributes those words to the prophet Isaiah. Elsewhere, the Gospel of Matthew associates Isaiah 7:14 with Christ’s birth (Matthew 1:22–23), and again these quotations are ascribed directly to Isaiah. This continuity of citation across the New Testament underscores the understanding that the entire book derives from one author inspired by God.

Manuscript and Archaeological Support

Ancient manuscripts, particularly the Great Isaiah Scroll from the Dead Sea Scrolls, contain all sixty-six chapters in a mostly unified text with limited textual variation. This continuity suggests that the community which preserved Isaiah did not view it as a patchwork of multiple authors but rather as a single composition from the same prophet. The high degree of agreement with later copies of Isaiah shows that scribes carefully handed down the text through the centuries.

Several archaeological artifacts provide support for the historical details in Isaiah. For instance, the Taylor Prism (also called the Sennacherib Prism) describes the Assyrian campaign against Judah under King Hezekiah, paralleling Isaiah’s account (Isaiah 36–37). Excavations in Jerusalem revealing the massive broad wall and structures linked to Hezekiah’s preparations for Assyrian invasion (2 Chronicles 32:3–5) further confirm the historical background.

Some finds even raise the possibility of a signature seal that may reference the prophet Isaiah. Although interpretations vary, a bulla discovered near another ancient seal belonging to King Hezekiah includes inscriptions that might be read to indicate “Isaiah the prophet,” offering a fascinating potential tie to the biblical figure.

Consideration of Multiple Authorship Theories

A number of modern scholars propose that the Book of Isaiah might be the work of two or three distinct writers (commonly referred to as “Deutero-Isaiah” for chapters 40–55 and “Trito-Isaiah” for chapters 56–66). These theories often center on stylistic, thematic, and historical differences, arguing that predictive prophecies about the Babylonian captivity or the Persian king Cyrus (Isaiah 44–45) must have been written later.

However, from the traditional perspective, these predictive elements fit the biblical theme of genuine prophecy—God revealing future events through His chosen messenger. The Book of Isaiah consistently frames foreknowledge as divine revelation, rather than later editorial insertion. Jesus and the writers of the New Testament likewise quote from both the earlier (Isaiah 1–39) and later sections (Isaiah 40–66) without any suggestion of separate authorship.

Conclusion

The testimony of the text itself, the unified witness of the Dead Sea Scrolls, the continuity of New Testament citations, and corroborating historical records point toward a single primary author, Isaiah son of Amoz. While debates about multiple authorship persist in modern scholarship, the weight of evidence—biblical, textual, historical, and archaeological—overwhelmingly supports the authorship of one prophet in the 8th century BC who spoke under divine inspiration about the geopolitical events of his time and beyond.

In sum, the Book of Isaiah stands as a cohesive work, shaped by the extraordinary prophetic ministry of Isaiah. Its message spans judgment and hope, calling readers to trust in the sovereignty of God and anticipating the coming of the Messiah.