The word “Trinity” is first recorded in the writings of Theophiles, the bishop of Antioch, to describe the mystery of One God in Three Persons, Father, Son, and Holy Spirit. And according to the ecclesiastical writer Tertullian, by the year 211, the signing of oneself with the sign of the cross, with the sign of the Trinity, had become a well-established custom of the Christian faithful.
“Yahweh is the true God and there is no other” (Dt. 4:35). God is One and has One nature (cf. Is.40:25-28; 43:10-13; 44:6-8; 1 Chron. 17:20; Mk. 12:29; 1 Cor. 8:4-6). There are Three Persons in One God, the Father, the Son, and the Holy Spirit. There is no confusion, change, division, nor separation between the Persons of the Trinity.
The Three Persons are distinct in their relations of origin: The Father generates, the Son is eternally begotten (Jn. 1:1-4f) and the Holy Spirit eternally proceeds from the Father and the Son (cf. Jn. 15:26).
In Genesis 1:26 we read in the story of creation: “Then God said: ‘Let us make man in our image,after our likeness.” In Genesis 3:22 we read: “Then the Lord God said, ‘See, the man has become like one of us…’” Who is this us? Who is this our?
In Genesis 18:1-3 many of the early Fathers of the Church saw the foreshadowing of the Trinity. Abraham meets three mysterious men (understood to be three divine persons or guests) whom he addressed by the singular as opposed to the plural, phrase, “My Lord” (a title most often reserved by the Jews for God). When studying the shifting back and forth between the three divine guests and Yahweh, we find something of great interest. At times Yahweh represents the three, at times Yahweh is one of the three, at times all the three refer to a single divine being. When taken as a whole, we can see why the Church Fathers often saw the foreshadowing of the Trinity in this passage.
In the Hebrew Scriptures, the Old Testament, God is referred to as Yahweh or Elohim, Elohim being translated as God and Yahweh being translated as Lord. What is of particular interest is that Elohim is a plural noun for God. The name Elohim indicates a oneness and a plurality. Therefore, Elohim indicates a oneness and a plurality in God. For the Christian, there is one God in three persons or modes of expression; there is a “oneness,” yet a “plurality.” The Hebrew Scripture’s, the Old Testament’s, name for
God attests to the plurality of persons in the one God!
At the baptism of Jesus in the Jordan we hear: “When Jesus had been baptized he at once came up from the water, and suddenly the heavens opened and he saw the Spirit descending like a dove and coming down on him. And suddenly there was a voice from heaven, ‘This is my Son, the Beloved; my favor rests on him’” (Mt. 3:16f). Right at his baptism the Trinity was manifested to the world: The voice is the Father, Jesus is the Son, and the image of the dove is the Holy Spirit.
At the Transfiguration Jesus is manifested in the midst of a cloud casting a shadow: “A bright cloud covered [Moses, Jesus, and Elijah] with a shadow, and from the cloud came the voice which said, ‘This is my beloved Son in whom I am well pleased. Listen to him” (Mt. 17:5). The voice is that of the Father, the beloved one is Jesus, and the cloud covering Jesus with a shadow is the Holy Spirit (Note that throughout the Hebrew Scriptures, particularly in Exodus, Numbers, and Deuteronomy, a cloud or a shadow represents God’s presence).
Before Christ’s ascension he reminded his apostles to go throughout the world and baptize in the“name of the Father, and of the Son, and of the Holy Spirit” (Mt. 28:10). Notice Jesus says to baptize in the “name” (singular) and not the “names” (plural) “of the Father, and of the Son, and of the Holy Spirit. There is one God, yet three Persons within that one God.
In the Gospel of Luke and the Acts of the Apostles, the sacred writer emphasizes the theme that in the Hebrew Scriptures the Father was most apparent, in the Christian Scriptures, the New Testament, Jesus became the center of attention, and in the acts of the early Church, the presence of the Holy Spirit was the main character. Obviously all three persons of the Trinity are present in each, yet the revelation of the Trinity took place through the process of revelation.
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