Theology Example (THEO)

This tutorial shows how FiveLoaves.ai uses OWLGraph to model the Bible as a theological knowledge graph — the first production use case for OWLGraph.

The Challenge

Existing Bible software treats Scripture as flat text with manual cross-references. A pastor preparing a sermon on Isaiah 53 has no systematic way to:

Trace prophecy-fulfillment chains across testaments
Navigate typological relationships (Adam → Christ, Passover → Crucifixion)
Query thematic connections ranked by ontological distance
See how different theological traditions interpret the same passage

The Ontology

FiveLoaves defines a theological ontology that captures the structure of biblical knowledge:

@prefix theo: <http://fiveloaves.ai/ontology#> .
@prefix owl: <http://www.w3.org/2002/07/owl#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

# === Core Classes ===
theo:Scripture a owl:Class .
theo:Passage a owl:Class ; rdfs:subClassOf theo:Scripture .
theo:Prophecy a owl:Class ; rdfs:subClassOf theo:Passage .
theo:Fulfillment a owl:Class ; rdfs:subClassOf theo:Passage .
theo:Parable a owl:Class ; rdfs:subClassOf theo:Passage .

theo:Person a owl:Class .
theo:BiblicalFigure a owl:Class ; rdfs:subClassOf theo:Person .
theo:Prophet a owl:Class ; rdfs:subClassOf theo:BiblicalFigure .
theo:Apostle a owl:Class ; rdfs:subClassOf theo:BiblicalFigure .
theo:Patriarch a owl:Class ; rdfs:subClassOf theo:BiblicalFigure .

theo:Place a owl:Class .
theo:City a owl:Class ; rdfs:subClassOf theo:Place .
theo:Region a owl:Class ; rdfs:subClassOf theo:Place .
theo:Nation a owl:Class ; rdfs:subClassOf theo:Place .

theo:Theme a owl:Class .
theo:Covenant a owl:Class ; rdfs:subClassOf theo:Theme .
theo:Event a owl:Class .
theo:Book a owl:Class .

# === Disjointness ===
theo:Person owl:disjointWith theo:Place .
theo:Prophecy owl:disjointWith theo:Fulfillment .

# === Object Properties ===
theo:fulfills a owl:ObjectProperty ;
    rdfs:domain theo:Fulfillment ;
    rdfs:range theo:Prophecy .

theo:fulfilledBy a owl:ObjectProperty ;
    owl:inverseOf theo:fulfills .

theo:typifies a owl:ObjectProperty ;
    rdfs:domain theo:BiblicalFigure ;
    rdfs:range theo:BiblicalFigure .

theo:typifiedBy a owl:ObjectProperty ;
    owl:inverseOf theo:typifies .

theo:locatedIn a owl:ObjectProperty, owl:TransitiveProperty ;
    rdfs:domain theo:Place ;
    rdfs:range theo:Place .

theo:partOfCovenant a owl:ObjectProperty ;
    rdfs:domain theo:Event ;
    rdfs:range theo:Covenant .

theo:hasTheme a owl:ObjectProperty ;
    rdfs:domain theo:Passage ;
    rdfs:range theo:Theme .

theo:references a owl:ObjectProperty, owl:SymmetricProperty ;
    rdfs:domain theo:Passage ;
    rdfs:range theo:Passage .

theo:inBook a owl:ObjectProperty ;
    rdfs:domain theo:Passage ;
    rdfs:range theo:Book .

theo:mentions a owl:ObjectProperty ;
    rdfs:domain theo:Passage ;
    rdfs:range theo:BiblicalFigure .

# === Data Properties ===
theo:name a owl:DatatypeProperty ; rdfs:range xsd:string .
theo:reference a owl:DatatypeProperty ; rdfs:domain theo:Passage ; rdfs:range xsd:string .
theo:text a owl:DatatypeProperty ; rdfs:domain theo:Passage ; rdfs:range xsd:string .
theo:testament a owl:DatatypeProperty ; rdfs:domain theo:Book ; rdfs:range xsd:string .
theo:tradition a owl:DatatypeProperty ; rdfs:range xsd:string .

Loading Data

# Insert Isaiah 53 as a Prophecy
curl -X POST http://INSTANCE/mutate?commitNow=true \
  -H "Content-Type: application/json" \
  -d '{
    "set": [{
      "uid": "_:isa53",
      "dgraph.type": "Prophecy",
      "reference": "Isaiah 53:5",
      "text": "But he was pierced for our transgressions...",
      "hasTheme": { "uid": "_:atonement" },
      "inBook": { "uid": "_:isaiah" },
      "mentions": { "uid": "_:servant" }
    },
    {
      "uid": "_:matt2728",
      "dgraph.type": "Fulfillment",
      "reference": "Matthew 27:28-31",
      "text": "They stripped him and put a scarlet robe on him...",
      "fulfills": { "uid": "_:isa53" },
      "hasTheme": { "uid": "_:atonement" },
      "inBook": { "uid": "_:matthew" }
    },
    { "uid": "_:atonement", "dgraph.type": "Theme", "name": "Atonement" },
    { "uid": "_:isaiah", "dgraph.type": "Book", "name": "Isaiah", "testament": "Old" },
    { "uid": "_:matthew", "dgraph.type": "Book", "name": "Matthew", "testament": "New" },
    { "uid": "_:servant", "dgraph.type": "Prophet", "name": "Suffering Servant" }
  ]}'

Automatic inferences:

Isaiah 53:5 gets types: Prophecy, Passage, Scripture (hierarchy)
Matthew 27:28-31 gets types: Fulfillment, Passage, Scripture (hierarchy)
fulfilledBy edge created on Isaiah 53:5 → Matthew 27:28-31 (inverse of fulfills)
Suffering Servant gets types: Prophet, BiblicalFigure, Person (hierarchy)
references is symmetric: both passages reference each other

Querying

# All Scripture about Atonement (Prophecies AND Fulfillments)
{
  atonement(func: type(Scripture)) @filter(has(hasTheme)) {
    reference
    text
    dgraph.type
    hasTheme @filter(eq(name, "Atonement")) { name }
  }
}

# Prophecy-Fulfillment chains
{
  prophecies(func: type(Prophecy)) {
    reference
    text
    fulfilledBy {
      reference
      text
      inBook { name testament }
    }
  }
}

# All passages mentioning BiblicalFigures (Prophets, Apostles, Patriarchs)
{
  passages(func: type(Passage)) {
    reference
    mentions @filter(type(BiblicalFigure)) {
      name
      dgraph.type
    }
  }
}

# Transitive location: places in a region
{
  places(func: eq(name, "Jerusalem")) {
    name
    locatedIn* { name dgraph.type }
  }
}

Why This Works

The ontology captures what theologians already know — that prophecy and fulfillment are both kinds of scripture, that typology is a directional relationship, that location is transitive. OWLGraph makes these relationships queryable without hand-coding the logic.

When the FiveLoaves AI agent prepares a sermon, it queries OWLGraph for the passage context, walks the prophecy chains, follows typological links, and gathers cross-references — all through standard graph queries on materialized data.