On the feast of Saint Nicholas, 6 December 1273, Aquinas underwent an experience while celebrating Mass in Naples after which he stopped writing altogether. Pressed by his companion Reginald of Piperno to continue, he answered, in the account transmitted by the early biographers, that after what he had seen everything he had written seemed to him as straw. The Summa broke off in the middle of the treatise on penance, and Aquinas died three months later on the way to the Council of Lyon. The work's afterlife was turbulent before it was triumphant.
In 1277 the bishop of Paris condemned a list of propositions that touched positions associated with Aquinas; the condemnation was later annulled for his teaching, and his canonisation in 1323 settled his orthodoxy. The Dominican order adopted his doctrine, and by the sixteenth century the Summa had displaced Peter Lombard's Sentences as the text on which theologians lectured, with commentators such as Cajetan writing at its side.
At the Council of Trent it stood among the works consulted on doctrine, and in 1879 the encyclical Aeterni Patris made Thomism the recommended framework of Catholic philosophy, securing the Summa's place at the centre of seminary education. Its questions on law, conscience and just war remain live references in ethics well beyond theology.