This is a little late in context but I want to get back to the original discussion about the Trinity. This is a little long so apologies, but I pray you take the time to consider what I present.
You state that the only reason the church supports the idea of the trinity is that it is “doctrine” as though there is no Scriptural support. But there is a wealth of Scripture already quoted above that I will add to:
15 He is the image of the invisible God, the firstborn of all creation. 16 For by him all things were created, in heaven and on earth, visible and invisible, whether thrones or dominions or rulers or authorities—all things were created through him and for him. 17 And he is before all things, and in him all things hold together. 18 And he is the head of the body, the church. He is the beginning, the firstborn from the dead, that in everything he might be preeminent. 19 For in him all the fullness of God was pleased to dwell,
“By Him (Jesus) all things were created”, but God the Father is the creator.
“all things were created…”for Him,” yet in the Old Testament clearly all things were created for the Father, not the Son.
“He is before all things” yet only God is eternal. Time is a created construct but Jesus was there before all created things, so if Jesus was present before time existed He must be eternal, and only God is eternal.
“In Him all things hold together”, yet it is God who created and sustains the universe.
“In him all the fullness of God is pleased to dwell” How could anyone but God contain all the fullness of God?
This last point is reiterated in Colossians 2:9:
“ For in him the whole fullness of deity dwells bodily,”
clearly indicates that Jesus is deity incarnate.
“Long ago, at many times and in many ways, God spoke to our fathers by the prophets, 2 but in these last days he has spoken to us by his Son, whom he appointed the heir of all things, through whom also he created the world. 3 He is the radiance of the glory of God and the exact imprint of his nature, and he upholds the universe by the word of his power. After making purification for sins, he sat down at the right hand of the Majesty on high”
Once again, Jesus was at the creation of the world and through Him the world was created. Jesus is the “exact imprint of His nature” speaks for itself. And finally once again it is Jesus who upholds the universe by His power, but that clearly in the OT was God’s role. This can only be true if Jesus is deity.
But of the Son he says,
“Your throne, O God, is forever and ever,
the scepter of uprightness is the scepter of your kingdom.
9 You have loved righteousness and hated wickedness;
therefore God, your God, has anointed you
with the oil of gladness beyond your companions.”
“You, Lord, laid the foundation of the earth in the beginning,
and the heavens are the work of your hands;
11 they will perish, but you remain;
they will all wear out like a garment,
12 like a robe you will roll them up,
like a garment they will be changed.
But you are the same,
and your years will have no end.”
God says to the Son, “Your throne, O God, is forever and ever.” God is calling His Son, God.
Then God claims that Jesus laid the foundation of the earth, so Jesus is the creator. And if the years of Jesus have no end, He is eternal…but only God is eternal.
13 waiting for our blessed hope, the appearing of the glory of our great God and Savior Jesus Christ,
In the original Greek the section in bold type reads, “tou megalou theou kai soteros hemon” which literally is translated “To great God and Savior our.” Tou is the definite article, and hemon is the possessive pronoun, meaning that the words “great God and Savior” in between are to be treated as a single unit all referring to Jesus Christ. That is the original Greek grammar.
5 Have this mind among yourselves, which is yours in Christ Jesus, 6 who, though he was in the form of God, did not count equality with God a thing to be grasped,7 but emptied himself, by taking the form of a servant, being born in the likeness of men.
Jesus was in the form of God in his preincarnate state. This is not true of the angels. He was in the form of deity but emptied himself of his deity to take the form of man.
Thomas answered Him, “My Lord and my God!”
This is Thomas’s confession after seeing Jesus for himself, and Jesus does nothing to stop him from worshiping him. In every instance where an angelic being is worshipped in the Bible, the angels stop the act because only God is to be worshipped. Jesus does nothing. Thomas’s words in the Greek, by the way, read “ho theos mou kai ho kyrios mou” or “the God of me and the Lord of me”.
3 But Peter said, “Ananias, why has Satan filled your heart to lie to the Holy Spirit and to keep back for yourself part of the proceeds of the land? 4 While it remained unsold, did it not remain your own? And after it was sold, was it not at your disposal? Why is it that you have contrived this deed in your heart? You have not lied to man but to God.”
In this case Peter moves from seamlessly from accusing Ananias of lying to the Holy Spirit and lying to God. By lying to the Holy Spirit he was lying to God.
9 You, however, are not in the flesh but in the Spirit, if in fact the Spirit of God dwells in you. Anyone who does not have the Spirit of Christ does not belong to him. 10 But if Christ is in you, although the body is dead because of sin, the Spirit is life because of righteousness. 11 If the Spirit of him who raised Jesus from the dead dwells in you, he who raised Christ Jesus from the dead will also give life to your mortal bodies through his Spirit who dwells in you.
Look at these verses! Paul moves from the “Spirit of God” to “the Spirit of Christ”, to simply “Christ”. Then he goes back to “spirit of Him” and “His spirit” which are both referring to the spirit of God. Do we have multiple spirits inside of us, or is Christ in us? Clearly the natural reading of the text is that all references are to same deity, yet Paul invokes multiple members of the Godhead because while they are all different persons, they are one God.
Finally, in the NT the person of God is referred to in Greek as “ho theos” which literally means “the God”, and is how the authors generally referred to God the father. The NT term in Greek that we see as Lord when referring to Christ is usually Kyrios. In the Septuagint, the translation in the OT for YHWH is kyrios. Now kyrios can also mean Lord as in master, but look at Romans 10:9-13
9 because, if you confess with your mouth that Jesus is Lord and believe in your heart that God raised him from the dead, you will be saved. 10 For with the heart one believes and is justified, and with the mouth one confesses and is saved. 11 For the Scripture says, “Everyone who believes in him will not be put to shame.” 12 For there is no distinction between Jew and Greek; for the same Lord is Lord of all, bestowing his riches on all who call on him. 13 For “everyone who calls on the name of the Lord will be saved.”
The first “Lord” in verse 9 is Kyrios, repeated in verse 12. But then in verse 13 quoting the prophet Joel , Paul quotes Joel 2:32 an OT scripture where the word Lord is kyrios in the Septuigint translated from the original text in Hebrew which used the name of God YHWH! So Paul is saying that if you confess that Jesus is Lord/kyrios you will be saved because everyone who calls on the name of the Lord/kyrios/YHWH according to the OT prophet Joel will be saved. Paul is overtly stating that Jesus is kyrios and kyrios is YHWH.