Tertullian (ca. 160–220) and Thomas Aquinas (13th century) both defended faith as a justification for their Christian beliefs, but whereas Tertullian proudly defended faith even when it clashed with reason, Aquinas argued that there was a harmony between faith and reason — that the two could never clash. In this lecture, Dr. Mayhew will examine the views of each in detail and briefly discuss the continuing influence of their conceptions of faith and reason in the 21st century.