Article 8: The Old Testament—Law, Prophets, Writings, and Inspiration
The Old Testament stands as a large, complex tapestry of narratives, poetry, legal codes, genealogies, prophecies, and wisdom literature—written by numerous authors across a span of roughly a millennium. Yet, from a classical Christian perspective, this diverse collection speaks with a single divine voice: the Holy Spirit’s. Christians since the early church have consistently regarded all parts of the Old Testament, whether the Torah (Law), the Prophets, or the Writings, as inspired by God. To many modern readers, however, the question arises: Why would genealogies or historical chronicles hold the same weight as Isaiah’s “Thus says the Lord” or the soaring theology of the Psalms?
In this article, we focus on the biblical-theological reasoning behind the doctrine that all Old Testament books—Moses’ Pentateuch, the Historical books (Joshua, Judges, Samuel, Kings, etc.), the Wisdom literature (Psalms, Proverbs, Ecclesiastes, Job), and the Prophets—together form a body of Scripture that is fully inspired. We rely on Louis Gaussen’s exegesis, as found in Theopneustia, to illustrate why “Moses and the Prophets” can be taken as shorthand for “the entire Old Testament authored by God’s Spirit.” We then draw on Robert Preus’s observations of how 17th-century Lutheran Orthodoxy consistently upheld this stance, and Richard Muller’s analysis of parallel convictions among Reformed scholastics. By exploring the logic behind Gaussen’s claim that every Old Testament “writing” is “prophetic,” we will see how these ancient texts, in all their genres, unite to form the covenantal story that Christ and the apostles affirm as God’s living Word.
1. Introducing the Threefold Division of the Hebrew Bible
The Hebrew canon historically divides the Old Testament into three main sections:
- Torah (Law): The five books of Moses (Genesis, Exodus, Leviticus, Numbers, Deuteronomy).
- Nevi’im (Prophets): This includes the so-called Former Prophets (Joshua, Judges, Samuel, Kings) and the Latter Prophets (Isaiah, Jeremiah, Ezekiel, and the Twelve Minor Prophets).
- Ketuvim (Writings): A collection that encompasses Psalms, Proverbs, Job, the Megillot (Ruth, Song of Songs, Ecclesiastes, Lamentations, Esther), Daniel, Ezra-Nehemiah, and Chronicles.
By the time of Jesus, this tripartite division was recognized in Jewish tradition, but the New Testament often simplifies it into references like “Moses and the Prophets,” or “the Law, the Prophets, and the Psalms” (Luke 24:44). Modern English Bibles sometimes reorder these books differently (placing historical books together, wisdom books together, etc.), but the theological claim remains: all of them come under the rubric of Holy Scripture.
1.1 The Lord Jesus’ Use of “Moses and the Prophets”
Throughout the Gospels, Jesus frequently references “Moses and the Prophets,” treating them not as separate or unequal authorities but as the unified testimony of God’s plan. For instance, in Luke 16:29–31, He teaches that if people will not hear “Moses and the Prophets,” neither will they be persuaded by miraculous events. And in Luke 24:27, the resurrected Christ interprets “in all the Scriptures the things concerning Himself, beginning at Moses and all the Prophets.”
From a Christian vantage point, this usage implies that the entire Old Testament belongs to one sacred category: God’s authoritative Word. Louis Gaussen builds on such passages to argue that it is improper to suggest only certain “prophetic” portions (like Isaiah or Jeremiah) truly bear the Holy Spirit’s stamp, while the “historical” or “wisdom” books do not. The biblical usage of “the Prophets,” “Moses,” and so on, indicates a totality.
2. Gaussen’s Argument: All OT Parts Are Prophetic
2.1 The Claim in Theopneustia
In his 19th-century work Theopneustia, Louis Gaussen famously contends that all Old Testament books—no matter their genre—are “prophetic Scriptures.” He reads 2 Peter 1:19–21, where Peter declares that “no prophecy of Scripture comes from someone’s own interpretation … but men spoke from God as they were carried along by the Holy Spirit,” as applying to the total Old Testament. For Gaussen:
- The biblical authors do not restrict “prophecy” to explicitly future-predicting texts.
- The phrase “prophecy of Scripture” or “prophetic Scriptures” includes every canonical book, since the apostles collectively refer to them as “Moses and the Prophets” (Luke 16:29), or “the Law and the Prophets” (Matt. 22:40).
- Therefore, the entire Old Testament is “spoken by God” and “written by God,” through the mediation of inspired men.
What this means practically is that Joshua’s narratives, the genealogies in 1 Chronicles, the poetry of Psalms, the dialogues in Job, and the oracles of Nahum or Habakkuk are all equally part of the body that Peter calls “prophecy of Scripture.” In other words, though modern classification might treat them as history, wisdom, or worship lyrics, Gaussen maintains that from the Holy Spirit’s perspective, they are a single corpus of God-breathed utterances.
2.2 Mosaic Authorship and Prophetic Status
To some, it may feel intuitive to call Isaiah or Jeremiah “prophets,” but less so to call Moses the same. Yet biblical usage does exactly that. In Deuteronomy 18:15, Moses prefigures Christ by referring to a “prophet like me” whom the people must heed. The Old Testament also calls Moses a prophet—Hosea 12:13 identifies Moses as God’s prophet who led Israel out of Egypt. Thus, Gaussen notes, the so-called “historical” books of Moses (i.e., the Torah) are no less “prophetic” in biblical parlance than Isaiah’s oracles.
When Jesus references “Moses” (e.g., Mark 12:26) as the author of the Pentateuch, He endorses the notion that God spoke through him. In the same breath, Jesus lumps the Pentateuch with the rest of the Old Testament (“Moses and the Prophets”). Gaussen sees no leeway here: the five books of the Torah, loaded as they are with genealogies, laws, and narrative expansions, stand on the same footing of divine origin as Jeremiah’s oracles about Babylon.
2.3 Historical Books as Prophecy
One might object: Surely Joshua or Judges do not read like “prophetic” treatises. They appear to be historical. But to Gaussen, that distinction is modern or literary in nature. By the time of Jesus, the Jewish tradition already classified Joshua, Judges, Samuel, and Kings among the “Former Prophets.” Indeed, “Prophets” was the label for all these historical volumes prior to the Writings. This categorization suggests that just as Isaiah or Ezekiel delivered direct oracles, so the authors of these narratives spoke forth the Word of God.
In these so-called Former Prophets, God’s activity, promises, and judgments are described historically but carry the same “Thus saith the Lord” authority. They might recount Israel’s battles or moral failures, yet Gaussen sees them as under the Spirit’s superintendence. The effect is that each historical episode becomes part of a grand theological narrative orchestrated by God, not a mere human chronicle.
2.4 Psalms and Wisdom Literature
Gaussen similarly extends the “prophetic” label to the Psalms, Proverbs, Job, Ecclesiastes, and other Writings. Indeed, the New Testament calls David a prophet (Acts 2:30). Jesus quotes the Psalms with unwavering finality: “Is it not written in your law?” (John 10:34), calling Psalm 82 part of the “Law.” This interchangeability of “Law” and “Prophets,” “Psalms,” or “Scripture” indicates a holistic approach: all Old Testament words come from God’s mouth.
Hence, whether praising or lamenting, whether Solomon’s proverbs or Daniel’s apocalyptic visions, the entire Old Testament is the product of men “moved by the Holy Spirit” (2 Pet. 1:21). For Gaussen, no portion is excluded from that classification. He interprets the wide variety of forms—lament, wisdom sayings, liturgical poems, genealogies, royal annals, etc.—as expressions of the Spirit’s manifold ways of communicating.
3. “Moses and the Prophets”: Every Author Wrote by God’s Spirit
3.1 The New Testament Endorsement
Luke 16 depicts Jesus telling a parable about a rich man and Lazarus. At its climax, Abraham says to the rich man in torment: “They have Moses and the Prophets; let them hear them” (Luke 16:29). In context, “Moses and the Prophets” stands for the entire Scripture recognized in Jesus’ day. Then again in Luke 24:27, after His resurrection, Jesus expounds “in all the Scriptures the things concerning Himself, beginning with Moses and all the Prophets.”
- Here the phrase, “Moses and all the Prophets,” obviously does not confine itself to only “prophetic” texts in a narrow sense; it is Jesus’ summation of the entire Old Testament.
- Gaussen cites these passages to solidify the idea that “Moses and the Prophets” is biblical shorthand for the complete Old Testament canon.
3.2 Jesus’ Citation of Psalms as Part of “Law”
In John 10:34, Jesus quotes Psalm 82:6—“I said, You are gods”—and then remarks, “Is it not written in your Law?” Interestingly, He calls the Psalms “Law,” signifying that from a first-century Jewish perspective, the entire Old Testament could be viewed under the umbrella of “Torah” or as carrying the same authority as commands.
Gaussen sees this usage as demolishing any notion that only the Pentateuch or the official “Prophetic” books are truly God’s words. If even the Psalms, typically grouped among the Writings, share in that same binding authority, then all OT segments—Law, Prophets, Writings—stand equally as divine oracles.
3.3 Preus and Muller’s Observations
Robert Preus, studying 17th-century Lutheran Orthodoxy, notes that confessional statements in that tradition treat “Moses and the Prophets” as referencing the entire Old Testament. The “Formula of Concord” and other Lutheran documents frequently quote historical passages (like from Joshua or Chronicles) with the same “God-breathed” reverence as they do from Isaiah or Daniel. Meanwhile, Richard Muller finds that Reformed scholastic confessions—like the Helvetic Confessions or the Westminster Confession—do likewise, often enumerating the Old Testament books collectively as the Word of God.
In effect, post-Reformation theologians systematically endorsed the view that “Moses and the Prophets” is an all-inclusive reference. They recognized that the biblical categories of “the Law, the Prophets, and the Writings” or “Moses and the Prophets” or “Scripture” do not allow picking and choosing. The entire corpus is from God’s Spirit.
4. Historical vs. Modern Classifications
4.1 Modern “Secular” Historical Approach
Modern historical-critical scholarship often divides Old Testament texts into categories like “deuteronomistic history,” “priestly codes,” “wisdom tradition,” or “exilic vs. post-exilic redactions.” On one hand, such analysis can illuminate background contexts. On the other hand, Louis Gaussen would warn that if these classifications lead us to attribute certain large swaths to purely human editing or tradition-building, we risk undermining the principle that no portion of the Old Testament is devoid of direct divine authorship.
Gaussen does not oppose investigating how biblical books came together; he does, however, strongly oppose any conclusion that some books are more “inspired” than others. The uniform witness of Jesus and the apostles supports an integrated approach where all these categories—historical, legal, poetic—remain equally God’s speech.
4.2 Patristic, Medieval, and Reformation Tradition
Across patristic, medieval, and Reformation eras, Christian commentators generally treated the entire Old Testament with the same reverential stance. Church Fathers like Irenaeus or Augustine cited any OT book to defend doctrinal or moral positions, assuming uniform authority. Medieval doctors, though also reliant on Church traditions, still referred to each OT book as part of the unified canon. Then, with the Reformation, the principle became more explicit: if it is in the Hebrew Bible recognized by Christ and the apostles, it is “the Word of God.”
Robert Preus and Richard Muller show how thoroughly the Reformation confessions extended that principle: from the genealogies in Chronicles to the lamentations of Jeremiah, all books are normative for doctrine, reproof, and edification. The Reformation’s difference from the medieval approach was not that the Middle Ages disrespected any portion, but that the Reformation hammered out a confessional stance explicitly rejecting any additions or subtractions—Scripture alone. This served to reinforce Gaussen’s theme that every single portion of the Old Testament, from the earliest chapters of Genesis to the post-exilic narratives, is God-breathed.
5. Why This Doctrine Matters
5.1 The Coherence of Redemptive History
If certain OT segments were suspect or considered “merely human,” the unity of redemption’s story from Creation to Christ would unravel. Genesis sets the stage for the Fall, sin’s entrance, and God’s first promise of a deliverer. The “historical books” track the unfolding of that promise through Abraham, Israel’s formation, David’s monarchy, and the eventual exile. Meanwhile, the “wisdom books” deepen our understanding of righteousness, suffering, and worship, while the “prophetic books” herald the Messiah.
By acknowledging all these as equally from God, believers see a coherent tapestry, culminating in Jesus, who declared He came to fulfill “the Law and the Prophets” (Matt. 5:17). If entire sections were deemed less inspired, the continuity that leads to the New Testament would be fractured.
5.2 Practical Edification
The conviction that genealogies, historical details, or seemingly obscure laws remain God’s Word fosters careful reading and unexpected edification. For instance:
- Levitical purity laws can reveal aspects of God’s holiness and the structure of covenant worship.
- Chronicles’ genealogies cast light on the faithfulness of God through generations, linking David’s line to the Messiah.
- Esther’s narrative demonstrates God’s providential hand even when “the name of God” is not directly mentioned.
Hence, the Reformation tradition taught that all of Scripture (including the entire Old Testament) was “profitable for doctrine, reproof, correction, and instruction in righteousness” (2 Tim. 3:16), aligning with Gaussen’s stance.
5.3 Assurance of Uniform Authority
When controversies arise—ethical, doctrinal, or pastoral—the Church historically turned to any part of the Old Testament for guidance, treating it with the same trust as if reading Paul or John in the New Testament. For instance, Jesus cited Genesis 1–2 to establish marriage norms (Mark 10:6–9), Paul used the historical narratives of Abraham or Sarah to illustrate justification and Christian freedom (Romans 4, Galatians 4). If the Church doubted the inspiration of some texts but not others, such usage would be precarious.
Robert Preus underscores how Lutheran Orthodoxy, following Luther, did not segregate books into “vital revelations” vs. “secondary historical matter.” They cited genealogies or ritual laws just as forcefully as “prophetic pronouncements,” believing the entire Old Testament to be “God speaking.” Similarly, Richard Muller shows that the Reformed scholastics cited every part of the Old Testament—Torah, historical books, psalms, prophecies—when forming theological arguments, a direct application of their confessional stance on plenary inspiration.
6. Objections and Gaussen’s Responses
6.1 “Aren’t Many OT Texts Merely Human Records?”
Some critics note that the biblical authors themselves sometimes reference older documents (e.g., the “Book of Jashar” in Joshua 10:13) or genealogies compiled by scribes. For Gaussen, these references do not negate inspiration. Rather, they reflect the Holy Spirit’s freedom to employ existing sources or human research in producing a final, inerrant product. The fact that the chronicler used archival records does not hinder God from ensuring the text we now have is exactly what He intended.
6.2 “Psalms Are Personal Expressions of Emotion, So How Are They from God?”
The raw emotional dimension in Psalms—like David’s anguished pleas or exultant praises—may seem to be David’s own outpourings. Gaussen’s retort: that is precisely how God chose to reveal Himself—by letting David’s experiences and words serve as a divine-human expression of truth. We see David’s unique style, but the Holy Spirit oversaw the composition, so that these prayers become binding for worshipers across generations. Early Christians recognized the psalmic laments and praises as also the voice of the Messiah (e.g., Psalm 22’s depiction of Christ’s sufferings).
6.3 “What about Morally or Culturally Difficult Passages?”
Critics point to portions of the OT that describe violence, polygamy, or culturally distant customs. Gaussen’s stance is that every portion remains instructive; sometimes they are negative examples or contextual revelations of God’s justice. The Spirit’s authorship extends even to these accounts, preserving them in the canon for the Church’s wisdom and moral reflection. They do not become less “inspired” simply because they are challenging or culturally foreign.
7. Pastoral and Devotional Significance
7.1 A Comprehensive Resource for Believers
When Christians realize that the entire Old Testament is “written by God’s Spirit,” they no longer skip or minimize certain sections as less authoritative or relevant. This can open up new vistas for preaching:
- Expository sermons on genealogies can highlight redemptive continuity and divine faithfulness.
- Studies in Leviticus can deepen understanding of Christ’s atoning work.
- Explorations of Ecclesiastes or Job can give robust answers to questions about life’s meaning and suffering, confident these are not “human musings” alone, but God’s wisdom.
7.2 Fostering Deeper Bible Reading
For laity, approaching the Old Testament with the knowledge that it is fully God’s Word fosters a more engaged reading. The genealogies of 1 Chronicles or the repeated cyclical patterns in Judges become windows into covenant dynamics, showing God’s sovereignty or humankind’s repeated need for redemption. Believers find the same Holy Spirit who authored these texts also willing to illuminate them in the present day (1 Cor. 2:10–14).
7.3 Christocentric Understanding
A key perspective is that the entire Old Testament leads to Christ. Jesus and the apostles anchored messianic claims in the entire corpus—Moses, the Prophets, and the Writings. If some parts were less divinely authored, that unity collapses. But affirming each portion as part of a single, God-inspired tapestry clarifies why Luke 24:27 says Christ is found “in all the Scriptures.” Gaussen’s approach to the Old Testament underlines its thorough Christocentric anticipation, from Genesis’ promise of the Seed (Gen. 3:15) to Malachi’s expectation of the Lord’s coming (Mal. 3:1).
8. Conclusion: Embracing the Whole Old Testament as God’s Word
Louis Gaussen, along with many Reformation and post-Reformation theologians, argues unambiguously that every segment of the Old Testament—Law, Prophets, Writings—is “God-breathed.” The result is a thoroughly integrated canon in which genealogical records, historical episodes, psalms, wisdom sayings, and direct oracles are all part of the same living address from God. When the New Testament references “Moses and the Prophets,” it is not drawing a line between “inspired oracles” vs. “secondary writings”; it is summarizing the entire scope of Old Testament Scripture.
Robert Preus and Richard Muller confirm that Lutheran and Reformed traditions historically upheld this principle. Their systematic presentations, anchored in confessional documents, taught that no Old Testament verse is a mere human leftover or an incidental footnote. Instead, it all belongs to the Holy Spirit’s grand composition, culminating in Jesus Christ. Because of this, the Church has felt no hesitation in deriving doctrine, ethics, comfort, warnings, and eschatological hope from any corner of the Old Testament.
For believers today, this perspective not only deepens reverence for the Hebrew Scriptures but also unlocks them for spiritual growth, moral discernment, and theological clarity. The genealogies, far from being inert lists of names, show God’s providential weaving of generations. The historical books reveal how God’s covenant faithfulness runs through Israel’s cyclical struggles and triumphs. The wisdom and poetic books cultivate worship, reflection on life’s mysteries, and heartfelt prayers. And the explicit prophetic books proclaim God’s holiness and redemptive plan in a manner that resonates with every era’s spiritual longings.
In short, acknowledging the Old Testament—Law, Prophets, and Writings—as wholly inspired aligns us with the stance Jesus Himself took, as well as the consistent practice of the apostles and the Church thereafter. We see not a haphazard anthology but an intricately orchestrated library, each page breathed out by God. As we read, we enter the same covenant story that shaped Israel and points us forward to the Messiah, forging a unified biblical narrative from Genesis to Revelation. Whether in genealogies or in oracles, the voice we hear is ultimately one: the Spirit of the living God, revealing His character, His redemption, and His sovereign work throughout history for the salvation of the world.
