Tertullian

Quintus Septimius Florens Tertullianus, anglicized as Tertullian, (ca. 155–230) was a church leader and prolific author during the early years of Christianity. He was born, lived, and died in Carthage, in what is today Tunisia.

Tertullian denounced Christian doctrines he considered heretical, but later in life adopted views that came to be regarded as heretical themselves. He was the first great writer of Latin Christianity, thus sometimes known as the "father of the Latin Church".

He introduced the term Trinity, as the Latin trinitas, to the Christian vocabulary and also probably of the formula "three Persons, one Substance" as the Latin "tres Personae, una Substantia" (itself from the Koine Greek "treis Hypostases, Homoousios") and also the terms vetus testamentum ("old testament") and novum testamentum ("new testament").

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