Quintus Septimius Florens Tertullianus, anglicised as Tertullian, (c. 160 – c. 225) was a church leader and prolific author of early Christianity. He also was a notable early Christian apologist. He was the son of a Roman centurion. He was raised in Carthage as a pagan. and also probably 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")… (More on Tertullian)