December 6, 1273

Summa Theologica

Thomas Aquinas stops writing and leaves the Summa Theologiae unfinished

Aquinas stopped in the middle of writing about penance; the remaining sacraments and the last things were never written into his Summa.

Not 1270, and never finished

The Summa Theologiae was not completed in 1270 — or in any year of Aquinas's life. He went on composing it through 1273 and then stopped writing while teaching at Naples.

According to testimony preserved through the canonisation tradition, something extraordinary happened while he celebrated Mass on 6 December 1273; afterward he ceased writing and dictating.

The cessation is well attested, but the nature of his experience is not independently recoverable, and modern biographers also consider exhaustion or illness.

Where the text stops

The authorial text ends in the Tertia Pars at question 90, in the treatment of penance, leaving the remaining sacraments and intended final subjects unwritten.

Aquinas's own unfinished work has 512 questions and 2,669 articles. Counts of 614 questions and 3,125 articles include the Supplement and appendices.

He wrote or dictated no further part of the Summa, and died three months later.

The ending someone else supplied

A later Supplement assembled by Aquinas's followers from his earlier commentary on Peter Lombard's Sentences was added to printed versions. It is not a completion written by Aquinas.

Reginald of Piperno, his companion and secretary, is associated in later biography with Aquinas's final months, and reports that Aquinas refused his requests to resume writing.

The familiar statement that his writings seemed like “straw” comes from that biographical testimony, not from Aquinas's surviving written works.

Sources

Researched 23 Aug 2026 6 sources not yet audited Traditional date

How this was checked

Researched from the web into a fact sheet and rewritten from that sheet. This article has not yet had an independent model audit. How the pipeline works →

Traditional date. Conventionally dated here; the research places it at 1273-12-06.

What the sources leave uncertain

December 6, 1273 is the traditional date preserved in early biographical and canonization testimony; the cessation itself is well attested, but the nature of Aquinas’s experience is not independently recoverable.
The familiar statement that his writings seemed like ‘straw’ comes from biographical testimony, not from Aquinas’s surviving written works.
Composition began around 1265–1266; exact dating of some sections varies slightly among modern chronologies.