Saint Thomas Aquinas (1225–1274) was a Dominican friar, theologian, and philosopher, widely regarded as one of the Church’s greatest thinkers. His works, particularly the Summa Theologica, integrate faith and reason, exploring topics like the existence of God, morality, and the nature of the soul. Aquinas is known for his efforts to reconcile Christian theology with Aristotelian philosophy, offering a rational framework for understanding divine truths. His teachings greatly influenced Catholic doctrine and philosophy. St. Thomas was canonized in 1323 and declared a Doctor of the Church in 1567. His feast day is celebrated on January 28.

The Canadian Conference of Catholic Bishops (CCCB) has decreed that this is a Holy Day of Memorial to be observed in Canada.