Short answer
No, not as the Church later defined it, and many early Christians rejected that definition. The word "Trinity" first appears in Christian writing around the year 180. Church councils, meetings of bishops, fixed the doctrine in 325 and 381. Peter's first sermon in Acts calls Jesus "a man approved of God". The Ebionites, early Jewish followers of Jesus, held that he was a man chosen by God (﷾). Arius, a church teacher, taught that the Son was created and not equal to the Father. Whole peoples, like the Goths, took their faith from Arian teachers. And no prophet of the Old Testament ever taught the Trinity. They taught that God (﷾) is one. Islam teaches the same: God (﷾) is one, and Jesus was His messenger.
Full explanation
When the doctrine was defined
The first known use of the term is around the year 180. Theophilus of Antioch, a Christian bishop, called God, his Word and his Wisdom a triad, which means a group of three. About thirty years later, Tertullian, a Christian writer in North Africa, used the Latin word trinitas, meaning Trinity. He admitted that the simple, the ordinary believers, were alarmed by it. He said they were always the majority of believers. The Council of Nicaea in 325 declared the Son to be of one substance with the Father. The Council of Constantinople in 381 added that the Holy Spirit is worshipped with them. The historian R. P. C. Hanson describes the years between as a search for the doctrine, not the defence of an old one.
Theophilus calls God, his Word and his Wisdom a triad (Greek trias). It is the earliest known use of the term in Christian writing.
Tertullian defends the doctrine he calls the Trinity (Latin trinitas), and admits that the simple, who always make up the majority of believers, are alarmed by it, fearing that it divides the one God.
The creed opens: "We believe in one God, the Father Almighty, maker of all things visible and invisible". The council confessed the Son as begotten of the Father, true God of true God, and "of one substance" (homoousios) with the Father, and condemned those who said there was a time when he was not.
The council confessed the Holy Spirit as the Lord and Giver of life, who proceeds from the Father, and who with the Father and the Son together is worshipped and glorified.
A history of the Arian controversy from 318 to 381. Argues that it was not the defence of a settled orthodoxy against heresy, but a search in which the church's doctrine of God was worked out, and reached its final form only in 381.
- The first sermon
"A man approved of God"
Peter's first sermon in Acts.
- About 155
Second place, third place
Justin Martyr puts the Son in the second place and the Spirit in the third.
- About 180
"Triad"
Theophilus of Antioch gives the first known use of the term.
- About 210
"Trinitas"
Tertullian uses the Latin word, and admits most ordinary believers were alarmed by it.
- 325
Nicaea
The Son declared of one substance with the Father; Arius condemned.
- 381
Constantinople
The Holy Spirit to be worshipped with the Father and the Son.
- End of the 500s
The last Arian kingdom
The Visigoths of Spain give up the Arian faith.
The first preaching about Jesus
In the book of Acts, Peter's first sermon calls Jesus a man approved of God (﷾). Peter adds that God (﷾) "made" Jesus both Lord and Christ. His next sermon calls Jesus God's servant. In Acts, Paul, a Christian missionary of the first century, applies the psalm "this day have I begotten thee" to God (﷾) raising Jesus. The opening of Paul's letter to the Romans says Jesus was "declared to be the Son of God with power" by the resurrection. Bart Ehrman, a scholar of early Christianity, reads these lines as the oldest belief about Jesus: a man whom God (﷾) exalted. The first letter to Timothy, written in Paul's name, speaks of one God (﷾) and one mediator, the man Christ Jesus. A mediator is a go-between. Around 155, Justin Martyr, a Christian writer, wrote that Christians worship Jesus. But he placed the Son in the second place and the Spirit in the third.
“Ye men of Israel, hear these words; Jesus of Nazareth, a man approved of God among you by miracles and wonders and signs, which God did by him in the midst of you, as ye yourselves also know:”
“Therefore let all the house of Israel know assuredly, that God hath made that same Jesus, whom ye have crucified, both Lord and Christ.”
“The God of Abraham, Isaac, and Jacob, the God of our fathers, has glorified his Servant Jesus, whom you delivered up, and denied in the presence of Pilate, when he had determined to release him.”
“God hath fulfilled the same unto us their children, in that he hath raised up Jesus again; as it is also written in the second psalm, Thou art my Son, this day have I begotten thee.”
“Concerning his Son Jesus Christ our Lord, which was made of the seed of David according to the flesh; And declared to be the Son of God with power, according to the spirit of holiness, by the resurrection from the dead:”
Argues that the earliest followers of Jesus believed God exalted him and made him Son of God at his resurrection. Ehrman finds this view in older material that Paul and Luke preserve: Romans 1:3-4 and the sermons in Acts 2:36, 5:31 and 13:32-33. He holds that Paul and Luke themselves had moved beyond it.
“For there is one God, and one mediator between God and men, the man Christ Jesus;”
Justin says Christians worship the Maker of all, and worship Jesus Christ, having learned that he is the Son of the true God, holding him in the second place and the prophetic Spirit in the third.
What the prophets taught
Through the whole of the Old Testament, God (﷾) tells His people that He is one and that there is no God beside Him. Jesus gave the same words as the first of all the commandments. If the Trinity were as central as Christians say, we would expect it to appear there plainly. It does not.
“Hear, O Israel: The Lord our God is one Lord:”
“I am the Lord, and there is none else, there is no God beside me: I girded thee, though thou hast not known me:”
“And Jesus answered him, The first of all the commandments is, Hear, O Israel; The Lord our God is one Lord:”
Jewish followers of Jesus
The Ebionites were Jewish followers of Jesus who kept the Law of Moses. The church writers who opposed them record that they held Jesus to be a man, born of Mary and made righteous by his virtue. Historians describe their Jesus as a righteous man whom God (﷾) chose.
Irenaeus reports that Cerinthus taught that Jesus was born of Joseph and Mary like other men, and that the Christ came down on him at his baptism. He says the Ebionites held a similar view of the Lord, used only the Gospel of Matthew, rejected Paul as an apostate from the Law, and kept the Law and its customs.
Eusebius says the Ebionites regarded Jesus as a plain and common man, justified only because of his superior virtue. Another group of them accepted his virgin birth but still denied that he existed before his birth as God.
Surveys the forms of Christianity that lost out to the church that became orthodox. Describes the Ebionites as Jewish followers of Jesus who kept the Law of Moses, rejected Paul, and held that Jesus was a full human being, a righteous man whom God chose and adopted as His son, not a divine being.
Arius and the Goths
Arius was a presbyter, a priest, in Alexandria in the fourth century. He taught that the Son had a beginning, so he was not eternal as the Father is. Nicaea condemned him in 325. But his view spread for decades with the support of emperors. The Goths, a Germanic people, took their Christianity from Arian teachers. The Visigoths of Spain held it until the end of the sixth century.
Socrates records the reasoning of Arius, a presbyter of Alexandria: if the Father begot the Son, the Son had a beginning, so there was a time when the Son was not.
The creed opens: "We believe in one God, the Father Almighty, maker of all things visible and invisible". The council confessed the Son as begotten of the Father, true God of true God, and "of one substance" (homoousios) with the Father, and condemned those who said there was a time when he was not.
Socrates records that the Goths under Fritigern took up the Christianity of the emperor Valens, who held the Arian view, and that their bishop Ulfilas taught them and invented Gothic letters to translate the Scriptures.
A history of the Goths. Describes how they took up Christianity in its Arian form in the fourth century, and how the Visigoths of Spain gave it up for Catholic Christianity only under King Reccared, at the end of the sixth century.
Later Christians who rejected it
In the sixteenth and seventeenth centuries, the Socinians rejected both the Trinity and original sin. Original sin is the teaching that every person is born sinful because of Adam's sin. The Socinians followed Fausto Sozzini, an Italian theologian. The Unitarian churches and the Jehovah's Witnesses reject the Trinity today.
The catechism of the Socinians, the followers of Fausto Sozzini (1539-1604). It teaches that there is one God, the Father alone, that Jesus is a true man and not God by nature, and that there is no such thing as original sin.
The founding statement of American Unitarianism. Channing argues from the Bible that God is one being and one person, the Father, and rejects the doctrine of the Trinity as unscriptural.
The Jehovah's Witnesses' own statement against the Trinity. It argues that the doctrine is not taught in the Bible, and that Jesus is God's Son and not God.
How Christians see it
Christians hold that the councils put into words what the apostles already believed. They point first to Jesus' command to baptise in the name of the Father, the Son and the Holy Ghost. But that verse names three together. It does not say they are one God.
“Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost:”
The creed opens: "We believe in one God, the Father Almighty, maker of all things visible and invisible". The council confessed the Son as begotten of the Father, true God of true God, and "of one substance" (homoousios) with the Father, and condemned those who said there was a time when he was not.
What the Qur'an says
The Qur'an tells Christians not to say "Trinity". It declares that there is no god but the One God (﷾). It describes the first disciples of Jesus as believers in Allah (﷾). They asked him to bear witness that they had submitted to God (﷾).
“O People of the Book! Commit no excesses in your religion: Nor say of Allah aught but the truth. Christ Jesus the son of Mary was (no more than) a messenger of Allah, and His Word, which He bestowed on Mary, and a spirit proceeding from Him: so believe in Allah and His messengers. Say not "Trinity": desist: it will be better for you: for Allah is one Allah: Glory be to Him: (far exalted is He) above having a son. To Him belong all things in the heavens and on earth. And enough is Allah as a Disposer of affairs.”
“They do blaspheme who say: Allah is one of three in a Trinity: for there is no god except One Allah. If they desist not from their word (of blasphemy), verily a grievous penalty will befall the blasphemers among them.”
“When Jesus found Unbelief on their part He said: "Who will be My helpers to (the work of) Allah?" Said the disciples: "We are Allah's helpers: We believe in Allah, and do thou bear witness that we are Muslims.”
Point by point
Matthew 28:19 — Gospel of Matthew, chapter 28, verse 19
“Go ye therefore, and teach all nations, baptizing them in the name of the Father, and of the Son, and of the Holy Ghost:”
Cited for
Jesus names the Father, the Son and the Holy Ghost together, so the apostles already knew God as three persons.
The response
The verse names three together. It does not say the three are one God, or that they are equal. In Acts, Peter tells people to be baptised in the name of Jesus Christ. And his sermons speak of Jesus as a man and a servant of God (﷾).
Where it lands — The verse lists three names. It does not teach that three are one God.
Creed of Nicaea, 325 CE — clause on the Son
The creed opens: "We believe in one God, the Father Almighty, maker of all things visible and invisible". The council confessed the Son as begotten of the Father, true God of true God, and "of one substance" (homoousios) with the Father, and condemned those who said there was a time when he was not.
Cited for
Nicaea did not invent anything. It defended the faith of the apostles against Arius, a newcomer.
The response
Before Nicaea, Justin worshipped the Son but still placed him second, and the Spirit third. Tertullian admitted that the simple, the majority of believers, were alarmed by the Trinity. After Nicaea, emperors backed Arian bishops for decades, and whole nations such as the Goths were Arian. The creed of 325 said only "And in the Holy Ghost". The Spirit was declared worshipped with the Father and the Son only in 381.
Where it lands — The doctrine was worked out between 325 and 381. It was not the settled belief of all Christians before then.
Perspectives
Mainstream Christian
The Trinity is the faith of the apostles. The councils of Nicaea and Constantinople did not invent it. They defended it against error and put it into exact words.
Jesus told his disciples to baptise in the name of the Father, the Son and the Holy Ghost.
Rebuttal
The verse does name the Father, the Son and the Holy Ghost. But it does not say they are one God or equal. In Acts, Peter tells people to be baptised in the name of Jesus Christ, and calls him a man approved of God (﷾).
The Council of Nicaea declared the Son of one substance with the Father.
Rebuttal
It did, but that came out of a long dispute, not an old teaching all Christians shared. Justin Martyr, a Christian writer, placed the Son second, and Tertullian said ordinary believers were alarmed by the Trinity. After Nicaea, emperors backed Arian bishops for decades, and whole nations like the Goths were Arian.
What historians record
The doctrine of the Trinity was worked out over centuries and reached its final form in 381. Many Christians, before and after, did not hold it.
The term first appears in Christian writing around 180. The doctrine was fixed at Nicaea in 325 and Constantinople in 381.
Around 213, Tertullian admitted that the simple were alarmed by the teaching of the Trinity. He called them the majority of believers.
Justin Martyr wrote that Christians worship Jesus Christ. They held him in the second place, he said, and the prophetic Spirit in the third.
The Ebionites, Jewish followers of Jesus, held that he was a man chosen by God.
Arius taught that the Son had a beginning, and the Goths received Christianity in its Arian form.
The Socinians rejected the Trinity and original sin. The Unitarians and Jehovah's Witnesses reject the Trinity today.
The years from 318 to 381 were a search for the doctrine of God. They were not the defence of a settled one.
The Islamic perspective
Jesus taught that God (﷾) is one, as every prophet before him did, and his first followers believed it. The Trinity came later.
Jesus named as the first of all the commandments that the Lord our God (﷾) is one Lord.
The earliest preaching in Acts calls Jesus a man approved of God (﷾) and God's (﷾) servant.
Peter says God (﷾) made Jesus Lord and Christ, and early wording in Acts and Romans ties his sonship to the resurrection. Bart Ehrman reads this as the first Christians' belief: a man whom God (﷾) exalted.
The Qur'an forbids saying "Trinity" and teaches that there is no god but the One God (﷾).
The Qur'an describes the disciples of Jesus as believers who submitted to God (﷾).