Theologian · Patristic
Tertullian
c. 155–c. 220 · Latin theology (North African)
Father of Latin theology, never canonized; he left the Catholic Church for the Montanist sect in later life, and his rigorist works were written outside it.
Carthaginian lawyer and the first great Christian writer in Latin. He coined the words “Trinity,” “person” and “substance” in their theological sense, defended Christians before the pagans, argued that heretics have no right to Scripture because the faith belongs to the churches founded by the apostles, and insisted on the resurrection of the flesh. He later embraced the Montanist “New Prophecy” and attacked the Church's forgiveness of grave sins.
Why he matters: The vocabulary of Latin Trinitarian and Christological dogma is his, and his Prescription against Heretics is the classic statement that Tradition, not private argument, settles the faith.
Where to be careful
His Montanist rigorism (no second repentance, no remarriage, no flight in persecution), his hostility to philosophy and to the Church's authority to forgive, and his materialist view of the soul are errors; Jerome and Augustine read him with care and so should we.
Documented positions
Where this thinker stands on each dispute the test covers.