World Religions › Medieval › Roman Catholic Church and the papacy
Thomas Aquinas
1225–1274· Founder, prophet or teacher· Judaism, Christianity & Islam
Historical recordConfirmed by archaeology, outside sources or contemporary records.
An Italian Dominican friar whose synthesis of Christian faith and Aristotle's philosophy became the backbone of Catholic theology.
See it on the World Religions map →What it is
Born near Aquino, Italy, around 1225, Thomas joined the new Dominican order against his family's wishes and taught at Paris. Using Aristotle's works, newly available in Latin from Greek and Arabic, he argued that faith and reason cannot truly conflict. His unfinished Summa Theologiae poses and answers thousands of questions, from God's existence (the 'Five Ways') to law and ethics. He drew openly on Muslim and Jewish thinkers, including Avicenna, Averroes and Maimonides. He was declared a saint in 1323.
Why it matters
His natural-law ideas shaped Western law and ethics, and his method still anchors Catholic teaching. In 1879 Pope Leo XIII made his thought the model for Catholic schools.
Life, legacy and sources
His writings survive in many manuscripts, some in his own hand; early biographies and canonization testimony; and university records from Paris and Naples.
Questions and debates
Late in 1273 he stopped writing, reportedly saying everything he had written seemed 'like straw' after a vision; whether the cause was spiritual or medical is unknown.
Connections (2)
▸Maimonides influenced Thomas AquinasHistorical record
The connection
Aquinas read Maimonides' Guide for the Perplexed in Latin and called him 'Rabbi Moses'. He adopted Maimonides' use of Aristotle to explain faith, some of his arguments for God's existence, and the view that some truths are known by reason, others only by revelation, though he disputed his strict limits on describing God.
When and where
The Guide was translated into Latin around 1240, probably in Paris; Aquinas used it in Paris and Italy, c. 1250s–1270s.
Historical evidence
Aquinas cites 'Rabbi Moses' by name in the Summa and other works, sometimes agreeing, sometimes disagreeing.
Questions and debates
Scholars debate how deep the influence went, versus shared debts to Aristotle and Muslim philosophers like Avicenna.
▸Thomas Aquinas became chief theologian of Roman Catholic Church and the papacyHistorical record
The connection
Aquinas's blend of faith and reason gradually became the church's standard theology. He was canonized in 1323 and named a Doctor of the Church in 1567. The Council of Trent drew heavily on his work, and Pope Leo XIII's 1879 encyclical Aeterni Patris made his thought the model for Catholic seminaries. Catholic natural-law teaching still relies on him.
When and where
Paris and Naples in the 1200s; later recognition in 1323 (canonization), 1567 (Pius V) and 1879 (Leo XIII).
Historical evidence
Papal documents, including Aeterni Patris and the 1917 Code of Canon Law, which told seminaries to teach by Aquinas's method and principles.
Questions and debates
Some of his ideas were caught up in the Paris condemnations of 1277; theologians still debate how strictly Catholics should follow his system today.