The word “Trinity” comes from the Latin noun “Trinitas” meaning “three are one.” The Trinity expresses the belief that God is one being made up of three distinct people who exist in co-equal essence and co-external communion as the Father, Son, and the Holy Spirit. The first recorded use of this word was by Theophilus, bishop of Antioch, who lived from 116 and 181 A.D. bishop Theophilus, in his letter to a friend, Autolykos, introduced the word Trinitas in his book 2, chapter 15 on the creation of the 4th day.
Although the term “Trinity” is not found in the Bible, most Bible scholars agree that its meaning is clearly expressed. These are some of the verses expressing the concept of the Trinity which is: Matthew3:16-17, Matthew28:19, John 14:16-17 Corinthians 13:14, Acts 232-33 John 10:30, John 17:11&21. The word “Trinity” began to be applied to them only in the course of later theological reflection.
However, the first clearest early expression of the concept came with Tertullian, a Latin theologian who wrote in the early third century. Tertullian had explained that the Father, Son, and Holy Spirit were “one in essence – not one in person”.
Saint Augustine, one of the greatest thinkers of the early church, described the Trinity as comparable to the three parts of an individual human being: mind, spirit, and will. They are three distinct aspects, yet they are inseparable and together constitute one unified human being.
The Christian took over the Jews’ uncompromising belief that: “The Lord our God is one God”. But they also soon came to the belief that Jesus is Lord. They applied to Christ Old Testament passage referring to Yahweh, the Lord; they worshipped Christ as God.
In worship and other activities, the Christians did not necessarily feel any tension between these two basic beliefs. But both Jews and pagans such as Celsus accused Christians of having two gods. Some Christians were also making an unacceptable statement about Christ. The issue of the Trinity (a later term) became an unavoidable problem. It was particularly difficult to resolve because of the influence of the Greek concept of unity, as perfect oneness, excluding any internal distinction.
Docetists and Jewish Christians, such as the Ebionites, saw no problem. The Docetists regarded Christ as merely a temporary appearance of God disguised as a human. The Ebionites saw Jesus as an ordinary person indwelt by God’s power at the baptism. Neither believed that Jesus Christ was truly God.
Some writers tried to safeguard both Monotheism and the deity of Christ with the logos theology which tended to be rather academic. It failed to give an adequate picture of the personal divinity of the logos, especially prior to creation.
Writers like Irenaeus and Tertullian developed it into an ‘economic’ doctrine of the Trinity-so called because it spoke of the relation between Father, Son and Spirit chiefly in term of the divine ‘economic’ or plan for the world, rather in term of the internal life of God in eternity. It emphasized the successive activities of Father, Son, and Spirit as God dealt with creation. It stresses that the one God was responsible for both creation and redemption, and thus countered Gnostic views.
in the late second and early third centuries, a backward-looking theology known as Monorchianism emerged in Asia Minor and flourished in the West. It was anxious to emphasize the divine unity or ‘monarchy’ (Greek, ‘single principle’). (the leader, Sabellius.) they claimed that God existed in different modes (so were sometimes called Modalists), but only in one mode at any one time. God different names Father, Son and Spirit described the different roles he played at different times.
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The Monarchians were also called Patripassians by their opponents because they taught in effect that the father (Latin, Passus) as the son. They felt they could not believe that God was one and that Christ was fully God, without rejecting the belief that God was always three.
The Monarchians were assailed on all sides-in Rome by Hippolytus and Novatian, Africa by Tertullian Alexandria by Origen. In writing a book to refute praxeas, perhaps a nickname for a roman bishop, Tertullian gave the Latin west a theological vocabulary that has hardly yet been bettered. He drew upon stoicism and Roman law for his language and taught that God was one being (substantia) but three concrete individuals (personae). The son and the spirit did not issue from his being like rays from the father by a division of his being, but as extensions from being, like rays from the sun. Tertullian’s theology was backed up by the Roman theologians and ensured that the western church was scarcely disturbed by the problems raised by Arius in the fourth century.
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Origen’s teaching dominated the east in the third and fourth centuries, against the Monarchians he insisted that father, son, and spirit were three eternally distinct persons (Greek hypostasis roughly the same as personae). The son owed his being eternal to the father (the eternal generation of the son) and was inferior to him. As a genuine son of the father, he was truly divine, but subordinate: the spirit was even lower. Origen’s ideas were deeply colored by middle Platonism, which graded existence into different levels. They pointed in various directions, and for his reason could be appealed to later by most parties in the Arian controversy.
Before the council of Nicaea (A.D. 325) most theologians viewed the son as in one way or another subordinate to the father.
Around A.d 250 a dispute between Dionysius of Rome and Dionysius of Alexandria illustrated the different approaches of the churches in West and East. The west was stronger on the unity of God and weaker on the permanent distinctness of the three, in the East the position was reversed.