In Jesus God came very near to us and revealed himself as the triune God. The Bible is the basis of the teaching about Trinity, although we do not find this term there. On the foundation of the Old Testament monotheism, the New Testament speaks about God as Father, Son and Holy Spirit and we can find statements about the relationships within God, among the three divine persons.
The origin of the understanding of the term person can be found in Christian Theology, in the endeavour to make the being of God and Jesus comprehensible. The original understanding was not material, nor was it understood as describing an autonomous subject. Characteristics of a person are the ability to have relationship, to love and to communicate.
The revelation of God’s triune nature is a process in the history of salvation. In the time of the Old Testament God laid the foundation for the right concept of his nature. He revealed himself as the only God and throughout the whole Old Testament we find his exhortation to strongly hold on to Monotheism.
Hear, O Israel! The LORD is our God, the LORD is one! You shall love the LORD your God with all your heart and with all your soul and with all your might. (Deuteronomy 6:4-5)
Thus says the LORD, the King of Israel and his Redeemer, the LORD of hosts: ‘I am the first and I am the last, And there is no God besides Me. Who is like Me? Let him proclaim and declare it; Yes, let him recount it to Me in order, From the time that I established the ancient nation. And let them declare to them the things that are coming And the events that are going to take place. Do not tremble and do not be afraid; Have I not long since announced {it} to you and declared {it?} And you are My witnesses. Is there any God besides Me, Or is there any {other} Rock? I know of none.’ (Isaiah 44:6-8)
The New Testament revelation of God’s nature does not change anything here,monotheism is an indisputable basis for the right understanding of Trinity.
During the Trinitarian discussions of the first centuries the right believe had to be defended against different false attempts to explain God’s nature on a level comprehensible for our human mind.
Monarchianism tried to keep the unity and uniqueness of God by explaining the three divine persons as three modes, three different ways of appearance of the one-personal God. Monarchianism therefore was called also Modalism. Another name for this teaching was Patripassianism. The creator of this term certainly wanted to show the consequence of this teaching: one would also have to believe that God the Father suffered and died on the cross, which is an absurdity when believing in a God who is almighty and eternal. The chief-representatives of this teaching were Noetus from Smyrna and Praxeas in the 2nd century AD and Sabellius in the 3rd century AD (therefore called also Sabellianism).
So it became necessary to explain the real difference between Father, Son and Holy Spirit more deeply.
Subordinatianism tried to explain the Trinity as a gradual order: God the Father stands above all as one who is inaccessible. A well-known representative of this teaching was Origen in the first half of the 3rd century AD. Subordinatianism said that the Son and the Spirit are divine in nature but clearly subordinated to the Father. Arius developed this teaching further in the end of the 3rd century AD and beginning of the 4th century AD. Arianism taught that in the beginning the Son was created by the Father and then together with the Father created the world. The consequence would be that the Son is a created being and not God. A further representative of this teaching was Eusebius from Nicomedia.
The Nicene Council in 325 AD dealt with this matter and declared that Father and Son are of the same nature (Greek: homoousion to patri). The Council of Constantinople 381 AD confirmed the formulations of Nicene and declared that also the Holy Spirit is of the same nature as Father and Son.
About the divine nature of Jesus
The New Testament teaches that Jesus is of divine nature, completely one and yet distinguished from the Father.
… from whom (the people of Israel) is the Christ according to the flesh, who is over all, God blessed forever. Amen. (Romans 9:5)
In the beginning was the Word, and the Word was with God, and the Word was God. He was in the beginning with God. All things came into being through Him, and apart from Him nothing came into being that has come into being. (John 1:1-3)
No one has seen God at any time; the only begotten God who is in the bosom of the Father, He has explained {Him.} (John 1:18)
In these verses we find essential statements for our topic. Here it speaks about the eternal existence and divinity of the second divine person, the Son. Word (Greek: logos) is the term John used for the Son. About the Word it is said that it was God and it was with God, which expresses on the one hand the equality of nature and on the other hand the difference between the persons.
In Jesus the Word became man. Neither the Father nor the Spirit became man but the Son, the One begotten from the Father, who has his eternal proceeding in the Father and since he is begotten the same nature as the Father has. Different variations of verse 18 exist in different manuscripts. Mostly we find the translation “the only begotten Son”, but the translation of the New American Standard-Version corresponds the text of the oldest and most reliable manuscripts of this verse and is a further unambiguous testimony of the divine nature of Jesus.
You can find a detailed and comprehensive essay about Jesus’ Divinity as a separate topic.
The Holy Spirit as a person
If you love Me, you will keep My commandments. I will ask the Father, and He will give you another Helper, that He may be with you forever; {that is} the Spirit of truth, whom the world cannot receive, because it does not see Him or know Him, {but} you know Him because He abides with you and will be in you. (John 14:15-17)
These things I have spoken to you while abiding with you. But the Helper, the Holy Spirit, whom the Father will send in My name, He will teach you all things, and bring to your remembrance all that I said to you. (John 14:25-26)
The Holy Spirit is called ‘Advocate’, the Greek word used here “parakletos” can be translated also as helper. The Spirit will teach and he will remind us of what Jesus said. No doubt that since Jesus spoke in this way about the Spirit he reveals him as a person and not as some kind of impersonal power.
There is an unambiguous philological proof for the Holy Spirit being a person, which cannot be translated into English. “Spirit” (Greek: pneuma) has neuter as its grammatical gender, but in the above quoted text the demonstrative pronoun which belongs to pneuma (Greek: ekeinos) does not have the neuter but the masculine form. Here the gender of the subject that is spoken about, replaces the grammatical one. The only possible explanation is that Jesus speaks about the Holy Spirit as a person.
In Acts we can find further hints at the being a person of the Spirit.
But a man named Ananias, with his wife Sapphira, sold a piece of property, and kept back {some} of the price for himself, with his wife’s full knowledge, and bringing a portion of it, he laid it at the apostles’ feet. But Peter said, Ananias, why has Satan filled your heart to lie to the Holy Spirit and to keep back {some} of the price of the land? While it remained {unsold,} did it not remain your own? And after it was sold, was it not under your control? Why is it that you have conceived this deed in your heart? You have not lied to men but to God. (Acts 5:1-4)
How can one lie to an impersonal power? One can lie to a real vis-à-vis, to someone whom I can have a relationship with and who demands and deserves honesty. Therefore it becomes clear that the apostles believed in the Holy Spirit as a person.
About the Trinity
When the Helper comes, whom I will send to you from the Father, {that is} the Spirit of truth who proceeds from the Father, He will testify about Me. (John 15:26)
Jesus sent the Advocate from the Father – all three Divine Persons are mentioned here. In John 14:26 it was the Father who was to send the Spirit, by this we can see that Jesus has the same authority. This is a strong proof for the divine nature of the Son and for the deep unity of the three Divine Persons.
But when He, the Spirit of truth, comes, He will guide you into all the truth; for He will not speak on His own initiative, but whatever He hears, He will speak; and He will disclose to you what is to come. He will glorify Me, for He will take of Mine and will disclose {it} to you. All things that the Father has are Mine; therefore I said that He takes of Mine and will disclose {it} to you. (John 16:13-15)
This is another strong expression of the unity in God as well as of the acting of and the interrelation between the three Divine Persons. These verses show the distinction of the three divine persons on the basis of the revelation of the one God.
The proceedings of the persons within the Trinity
When do we speak of the eternal procreation of the Son and the proceeding of the Spirit? Are these only ways of expression or do these words really describe the inner being of God? We have to admit that our human language is not perfect. Our understanding of words is the result of our experience. God’s eternal being is far beyond all human experience. Therefore every human language is (and must be) a very insufficient tool to describe the eternal God. However, we do not have another tool. In addition, even God used human language to reveal himself to us, knowing that his words would be misunderstood or even distorted.
Jesus came to reveal the Father. Therefore, his words cannot only be some ways of expressing himself according to the Jewish understanding. Revelation means that Jesus brought information about God’s being. Jesus spoke about a relationship as between father and son. We can understand this as a picture. But this picture has content that the Father begot the Son. The other way round is not possible. John called the Second Divine Person “Logos”, word. This presupposes that somebody speaks this word. The Logos has His origin in the Father.
There cannot be any difference between the three divine persons concerning their divine attributes. There cannot be any difference concerning omnipotence, omniscience or omnipresence. There cannot be a greater or a smaller person in God. If we neglect the differences concerning their relationships, no difference remains at all. Consequently, it is not sensible to speak about three divine persons. This way of thinking is a pre-form of Modalism. The three divine persons would not be eternal reality within God, but only different ways of God’s revelation to the world.
Furthermore, it is not possible to say that some biblical expressions concerning Trinity fit the Jewish way of thinking. John called Jesus the “only begotten God”(Greek: monogenes theos). This term fits neither the Jewish nor the Greek thinking. This term bears in itself a logical contradiction. Either he is begotten or he is God. This term was hard to understand. Therefore, some copiers thought that they had to “correct” this expression. Therefore, they rather corrected the Bible than their thinking. This expression is only sensible if we refer it to the eternal procreation of the Logos within Trinity. The procreation of the Son is an eternal process beyond time and space. Similar as the Sun sends constantly rays the Father begets the Son in a process without beginning and without end. The Father is the eternal origin of the Son. Both take part in the one and only indivisible God. The “priority” of the Father cannot be a priority in time. It cannot be a priority in importance or power either. It is only a priority in the origin.
Essential principle concerning the persons in the Trinity is that they differ only in their relation to one another, but in other things they are one. Therefore, when we say, that the Father loves us included we claim also the love of the Son and the Holy Spirit. When we say, that the Son is present in the community of those who believe in him, included we express also the presence of the Father and the Holy Spirit. When we say, that the Holy Spirit clothes us with power we must know, that he does this together with the Father and the Son. That the common operation of the three divine persons is yet attributed to one person reflects something from the role of the concerning person in the Trinity.
Altogether, we can see that the New Testament reveals us Jesus as ONE with the Father and yet distinguished. The expression “only-begotten” (Greek: monogenes) shows that the Son received Himself from the Father which does not speak about a time-point but about the relationship between them both. The Father is the origin of the Son, the Son proceeds eternally from the Father, and hence he is of the same eternal nature. The Holy Spirit is send into the world from the Father and the Son. He finds his being in the same origin, is of the same eternal nature and in the same way he takes part in the inner giving, receiving and unity of God.
In 1 Timothy 6:16 it says:
… who alone possesses immortality and dwells in unapproachable light…
Here it does not speak about his holiness only but also about his unfathomability. That we as God’s creatures cannot grasp His eternal nature with our mind cannot be a reason against Trinity. God lives in a different dimension than what we know. He revealed Himself in a mystery, which grants us more than we are able to ask and to expect. Hence, we are thankful that he showed us so much of himself. Even though we cannot understand him yet fully, the love and unity, which are his very nature, are given to us as clear guidelines for our life and acting here and now. God wants us to know him so that we can find a real and living relationship with him. The way to get there is open for everyone.