Lecture 2

2. Structure of Sacred Doctrine and the Incarnation

Summary
This lecture examines the organizational structures of Thomas Aquinas’s Summa Contra Gentiles and Summa Theologiae, comparing how each arranges the treatment of God (in Himself, as Maker, and as End). Berquist explains why the Incarnation is placed differently in each work—under ‘God as Maker’ in the SCG but under ‘God as End’ in the ST—and introduces the six central questions for understanding the Incarnation, particularly whether it was suitable and necessary for human redemption.

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Lecture Notes

Main Topics #

Two Structural Approaches to Sacred Doctrine #

Summa Contra Gentiles (Four-Book Structure)

  • Book 1: God in Himself (existence, substance, operation)
  • Book 2: God as Maker (creation, creatures, rational beings and angels)
  • Book 3: God as End (divine end of all things, general providence, special providence over man)
  • Book 4: Matters knowable by faith alone (Trinity, Incarnation, Sacraments, Last Things)
  • Uses a crisscross division between:
    • Things knowable by natural reason (Books 1-3)
    • Things knowable by faith alone (Book 4)
  • Originally framed for missionary dialogue with Jews and Muslims in Spain

Summa Theologiae (Three-Part Structure)

  • Prima Pars: God in Himself (including Trinity) and God as Maker
  • Secunda Pars: The motion of rational creatures toward God (virtues and moral theology)
  • Tertia Pars: Christ as the Way to God; His benefits to human race; Sacraments; Last Things
  • Expands and deepens the third part of the SCG (God as End)
  • Integrates faith-reason division within the three-fold division rather than separating them

The Three-Fold Division as Foundation #

All of sacred doctrine rests on understanding God as:

  1. God in Himself
  2. God as Principium (Maker/First Principle)
  3. God as End (Final Goal)

These three are present in both works but distributed differently.

Placement of the Incarnation: Two Perspectives #

In Summa Contra Gentiles: Incarnation falls under “God as Maker”

  • Justification: The Incarnation is “the greatest thing God made”
  • Every other miracle is ordered toward this one
  • Emphasizes the creative aspect of God becoming man

In Summa Theologiae: Incarnation falls under “God as End”

  • Justification: Christ is the via (way/road) by which we return to God
  • Christ as Savior is essential to humanity’s journey to its final end
  • Emphasizes the redemptive aspect and man’s orientation toward beatitude

Key Point: Neither placement is incorrect; they highlight different aspects of the mystery.

Key Arguments #

The Necessity and Suitability of the Incarnation #

Two Distinct Senses of “Necessary” (Aristotelian distinction)

  1. Absolute Necessity (sine qua non): That without which something cannot be at all (e.g., food for life)
  2. Conditional Necessity: That without which something cannot be well achieved (e.g., a horse for a long journey)

Applied to Incarnation:

  • Absolute sense: NOT necessary—God could have redeemed humanity in other ways
  • Conditional sense: NECESSARY—no more suitable way exists

Scripture’s Emphasis: The texts always connect the Incarnation to redemption from sin; Thomas inclines toward the position that God would not have become incarnate without sin.

The Six Central Questions about the Incarnation #

Thomas divides the first part of the Tertia Pars into six articles:

  1. Was it suitable for God to become flesh?

    • Foundation: God’s nature is goodness itself
    • Principle (from Dionysius): It belongs to the notion of good to communicate itself
    • Conclusion: The highest good communicates itself in the highest way—by uniting created nature to Himself in one person
  2. Was the Incarnation necessary for reparation of the human race?

    • Uses the Aristotelian distinction of necessity
    • God could have redeemed otherwise but chose the most suitable way
    • Augustine: “A more suitable way of healing our misery there was not”
  3. Would God have become incarnate without sin?

    • Scripture emphasizes connection to sin and redemption
    • Thomas inclines toward: No, not without sin
    • Others (like Scotus) argued yes, but Thomas follows scriptural emphasis
  4. Was Christ chiefly incarnated to take away original sin or actual sin?

    • Original sin affects all humanity (excepting Christ and the Virgin)
    • Thomas likely sees original sin as the chief target
  5. Was it suitable that God was incarnated from the beginning of the world?

    • Question of why the incarnation was delayed
  6. Should the incarnation have been deferred to the end of the world?

    • Timing and appropriateness of the historical incarnation

Important Definitions #

  • Via (ὁδός, via): The way or road; Christ as the way by which humanity returns to God
  • Hypostatic Union: The union of divine and human natures in one person (Christ)
  • Prologue (πρόλογος, prologus): Forward or introduction; specifically the opening statement of the Tertia Pars

Examples & Illustrations #

On Naming and Language #

  • We use “incarnate” (not “humanized”) following St. John’s Gospel
  • This is synecdoche: the part (flesh) standing for the whole (human nature)
  • Parallel: “The Word” is antonomasia—the name of the universal given to one outstanding particular

The Symbolism of Two Angels #

  • Gregory the Great: One angel at the head, one at the feet
  • Head angel represents divinity: “In the beginning was the Word”
  • Feet angel represents humanity: “The Word was made flesh”
  • Connection to synecdoche and antonomasia in describing Christ

On the Necessity of Understanding “Necessary” #

  • Aristotle’s lost dialogue on philosophy: Whether you philosophize or not, you must use reason
  • Similarly: Is it necessary to understand the word “necessary”?
    • If yes: you’ve already understood it
    • If no: you must understand it to show why it’s not necessary
  • Applied to Incarnation: Is it necessary? The answer itself requires understanding necessity

Contemporary Example on Humility and Belief #

  • Modern people struggle to believe in doctrines like the Real Presence
  • Even the risen Christ faced doubt: “Some doubted” (Matthew 28:17)
  • Humility is necessary for belief—the proud person overestimates his ability to judge and won’t submit his mind to those wiser
  • Belief (before understanding) is natural to man: we believe the Pythagorean Theorem before knowing its proof

Questions Addressed #

Why different structures in SCG vs. ST?

  • SCG: Apologetic work for missionaries; must separate what reason can access from faith-only truths
  • ST: Pedagogical work for students; can integrate both while showing how reason ascends toward faith
  • SCG emphasizes God as Maker (what He created); ST emphasizes God as End (where we’re going)

Why does the Incarnation appear in two different places?

  • SCG: Under “God as Maker” because the Incarnation is God’s greatest creative act
  • ST: Under “God as End” because Christ is our way back to God, our final destiny
  • Both are correct; they emphasize different theological perspectives on the same mystery

How can God become flesh without changing?

  • God Himself does not change; the human nature is newly united to the unchanging divine person
  • The creature is assumed; God is not diminished or altered

What role does humility play in understanding the Incarnation?

  • Humility removes the pride that prevents belief
  • The proud person judges things beyond his capacity and won’t submit to wiser minds
  • Faith requires receiving what we cannot initially comprehend through our own reason