Difficulty in understanding the Trinity was, and is today, commonplace, but its orthodoxy is unquestionably sound. It was an earlier theologian named Tertullian, who, at the turn of the third century, first coined the term Trinity. His description of the Godhead, tres Personae, una Substantia (three Persons, one Substance) is summarized in his work, Adversus Pracian (Against Praxeas). Tertullian did not invent the doctrine of the trinity, but rather had opportunity to present an explicit explanation in answering to Praxeas who believed that the Father and Son were one in the same person. Tertullian used the Scriptures to explain the Trinity and insisted that one portion of Scripture should not be interpreted contrary to another portion.
“But Scripture is not in such danger that you need to come to its help with your reasoning, lest it should seem inconsistent with itself. It is quite right both when it lays down that there is one God and when it shows that there are two, Father and Son, and it is self-sufficient”
Tertullian did not appear to make any grand theological oration, just simple logical explanations from Scripture. His predecessors presented the Trinity in terms that were mater-of-fact, indicating that Christians in the earliest years of church existence understood the concept. In simply stating what Christians believe, the second century apologist and bishop of Lyons, Irenaeus, plainly declared the Trinity in his works against heresy.
“The Church, though dispersed through our the whole world, even to the ends of the earth, has received from the apostles and their disciples this faith: She believes in one God, the Father Almighty, Maker of heaven, and earth, and the sea, and all things that are in them; and in one Christ Jesus, the Son of God, who became incarnate for our salvation; and in the Holy Spirit, who proclaimed through the prophets the dispensations of God.”
And earlier at the turn of the second century Ignatius, bishop of Antioch, clearly established in his salutations to the Ephesians that the will of the Father and the will of the Son were one in the same yet distinct persons. “…Elected through the true passion by the will of God the Father, and of our Lord Jesus Christ our Savior”
The Trinity concept survived to the time of Tertullian untainted. During Tertullian’s time, a Christian philosopher and theologian at the head of the catechetical school of Alexandria, Clement of Alexandria, also lectured quite clearly concerning the Trinity in his Exhortation to the Heathens:
“We the rational creatures of the Word of God, on whose account we date from the beginning; for “in the beginning was the Word.” Well, inasmuch as the Word was from the first, He was and is the divine source of all things; but inasmuch as He has now assumed the name Christ, consecrated of old, and worthy of power, he has been called by me the New Song. This Word, then, the Christ, the cause of both our being at first (for He was in God) and of our well-being, this very Word has now appeared as man, He alone being both, both God and man-the Author of all blessings to us; by whom we, being taught to live well, are sent on our way to life eternal.”
So even though the term “Trinity” originated with Tertullian, the concept of one God in three persons was evident from the earliest writings of the church fathers.
