"Tertullian, Sergius, and Cicero... the Three Verus Brothers."
(155-220 A.D.)
A prolific early Christian author from Carthage in the Roman province of Africa. He was the first Christian author to produce an extensive corpus of Latin Christian literature. 31 of his written works exist today.
He was raised in Africa and is thought to be the son of a Roman centurion. He may have become a lawyer, priest, or both. He became a Christian in 197 A.D. and married a Christian woman.
He was an early Christian apologist and a polemicist against heresy, including contemporary Christian Gnosticism. Tertullian has been called "the father of Latin Christianity" and "the founder of Western theology."
He originated new theological concepts and advanced the development of early Church doctrine. He is perhaps most famous for being the first writer in Latin known to use the term trinity (Latin trinitas).
(Origin of the Bible handout by my small group leader, February 8, 2023. Summarized from Wikipedia. Page 5.)
The terms Old Testament and New Testament came into use in the later part of the second century. Tertullian rendered diatheke into Latin by instrumentum (a legal document) and also by testamentum, and 'testament' has survived to this day. (The Origin of the Bible: Newly Updated by F. F. Bruce, J. I. Packer, Philip W. Comfort, and Carl F. H. Henry, 2020. Page 5.)