The very first verse of the Book of Revelation gives us a clue as to the answer:
“The revelation from Jesus Christ, WHICH GOD GAVE HIM to show his servants what must soon take place” (Revelation 1:1 NIV).
If Jesus was Almighty God, as Trinitarians claim, he would not have to be given the Revelation by God, he would already know it.
“And from Jesus Christ, who is the faithful witness, the first born from the dead . . . and has freed us from our sins by his blood” (Revelation 1:5 NIV).
Jesus cannot be Almighty God because he died, and Almighty God “never dies” (Habakkuk 1:12 NJB). So, while Jesus was dead, his Father, Almighty God, remained alive. There are no other options, God the Father had to be alive in order to be able to resurrect his Son, Jesus. And thus we read: “God resurrected this Jesus” (Acts 2:32 HCSB).
“And has made us to be a kingdom and priests to serve his God and Father” (Revelation 1:6 NIV).
Jesus is described as having “his God and Father”. Therefore, he cannot be equal to God the Father.
“‘I am the Alpha and the Omega,’ says the Lord God, ‘who is and who was and who is to come, the Almighty'” (Revelation 1:8 NASB).
The still very popular KJV translation omits the word “God” from Revelation 1:8. The four expressions, or titles, “the Alpha and the Omega”, “the Lord God”, “who is and who was and who is to come”, and “the Almighty” apply exclusively to God the Father of Jesus Christ. Trinitarians assert that Revelation 1:8 applies to Jesus Christ, but these facts exclude that possibility. The title “the beginning and the end” (Revelation 1:8) is spuriously added to the KJV text, so Trinitarians try to claim that makes Jesus to be Almighty God. That claim doesn’t carry any weight since that expression doesn’t appear in the earliest and best Greek manuscripts.
“I am the first and the last, and the living One; and I was dead, and behold, I am alive forevermore, and I have the keys of death and of Hades”—Revelation 1:17,18
Trinitarians assert that because Jesus has the title “the first and the last”, that means Jesus is Almighty God, who also has this same title (Isaiah 44:6). However, Kings Artaxerxes and Nebuchadnezzar are called by the titles “king of kings” (Ezra 7:12; Daniel 2:37), just as Jesus is also (Revelation 17:14;19:16). Obviously, these two kings are not Jesus Christ, even though the three share the title “king of kings”. Jesus and his Father share some titles, such as “Lord”, “Savior”. Humans are also referred to as saviors in the Bible, but they are are obviously neither God nor Christ (Judges 3:9,15; Neheniah 9:27; Obadiah 21, all NAB). “What God was, the Word was” (John 1:1c REB). Jesus is very much like his Father, but that does not mean that Jesus is Almighty, or is Yahweh, or is equal to his Father, as Trinitarians try to assert.
The fact that Jesus said “I was dead” is very powerful evidence against the Trinitarian claim that Jesus is “eternal”. Yes, Jesus is “alive forevermore” now, that is, he will never die again, but the Biblical fact remains that “Christ died for our sins” (1 Corinthians 15:3). As far as the Bible is concerned, there is no such thing as any so-called “dual nature” of Christ, whereby the supposed human part of Christ died, but his God part remained alive. That notion is Trinitarian fiction.
When we honestly and objectively consider Revelation chapter 1, we see that the Trinity doctrine not only finds no support, and the assertions in it are completely debunked by the Scriptures.