Some Trinitarians teach that the New Testament not only teaches that Jesus is God, but additionally, that it specifically teaches that one must believe that Jesus is God in order to be saved.
Unitarians should examine this claim, because obviously, if it is true, then they will not be saved. Trinitarians should examine it, because if it is not true, repeating this claim would be preaching a false Gospel, which is a serious sin in the New Testament (Galatians 1:8-9), and also causing strife for those who do not believe what would ultimately be a false doctrine.
The most common passage appealed to by advocates of this doctrine is from John chapter 8, in which Jesus says, "unless you believe that I am he, you will die in your sins":
John 8:24 (WEB)
24 I said therefore to you that you will die in your sins; for unless you believe that I am he, you will die in your sins.
Some translations render the above passage as, "unless you believe that I am, you will die in your sins", with some even capitalizing "I AM" (NABRE, NCB, JUB, ISV, CJB). In this, they are attempting to make a connection to the following passage from Exodus chapter 3:
Exodus 3:14
14 And God said unto Moses, I Am That I Am: and he said, Thus shalt thou say unto the children of Israel, I Am hath sent me unto you.
Above, God identifies Himself to Moses as "I Am". So, Trinitarians who use John 8:24 to argue that unless someone believes that Jesus is God they will not be saved are asserting that in John chapter 8, Jesus is claiming to be the "I Am That I Am" from this passage, and also that if people do not believe that, they will die in their sins.
In response, a Unitarian would say that in John 8:24, Jesus says egō eimi ("I am", "I am he", "I am the one"). The Jews, after hearing this, ask Him, "Who are you?" (John 8:25), demonstrating they did not understand this to be a divine claim at all, despite assuming the worst of Him, and the Lord responds, "Even the same that I said unto you from the beginning" (John 8:25).
So, what was Jesus saying to people "from the beginning" in the Gospel of John? That He was the "I Am" of Exodus? Or, that He was Yahweh? No, rather, if one examines the first time that Jesus uses the phrase egō eimi in John's Gospel, they will see Him teaching that He is the Messiah:
John 4:25-26
25 The woman saith unto him, I know that Messias cometh, which is called Christ: when he is come, he will tell us all things.
26 Jesus saith unto her, I that speak unto thee am he.
In verse 26 above, Jesus says egō eimi (ἐγώ εἰμι), and in context, it is Him identifying Himself as the Messiah. After this first instance, Jesus goes on to use the phrase for the same purpose throughout the Gospel of John (John 8:24, 8:28, 8:58, 13:19, 18:4-6). The Gospel of John also records people specifically looking for a prophet to come (John 1:19-21, 6:14, 7:40), and so Jesus is essentially saying, "I am the one, the one you are looking for, the Messiah".
Additionally, near the end of John's Gospel, he gives a purpose statement, which says:
John 20:30-31
30 And many other signs truly did Jesus in the presence of his disciples, which are not written in this book:
31 But these are written, that ye might believe that Jesus is the Christ, the Son of God; and that believing ye might have life through his name.
According to the above, John's thesis is that Jesus is the Christ. That is consistent with Jesus making the "I am" statements throughout, identifying Himself as the Christ. This is what is happening in the passage in question from John chapter 8. Jesus is not, in that passage, claiming to be the "I Am" of Exodus 3:14.
The "I Am" interpretation of John 8:24 also runs into the problem that the Apostles and followers of Jesus never preach that He is God to anyone. In the book of Acts, what His followers preach instead communicates that He is distinct from God, and not God (Acts 2:22, 2:36, 3:13, 3:26, 4:10, 5:30-31, 10:38-42, 13:37-38, 17:30-31). Nowhere in the Epistles does any writer so much as teach that He is God, let alone that one must believe that He is God to be saved. However, they do teach John's purpose statement - that He is the Christ - over and over again. If there is one united thesis in the New Testament, it would be that Jesus is the prophesied Jewish Messiah. So, that belief is what is being referred to in John 8:24. Such a conclusion fits the context of John's Gospel, and the rest of the New Testament.
The only other passage commonly appealed to in order to teach that one must believe that Jesus is God to be saved is the following from Romans chapter 10:
Romans 10:9-13 (WEB)
9 that if you will 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 unto righteousness; and with the mouth confession is made unto salvation.
11 For the Scripture says, "Whoever believes in him will not be disappointed."
12 For there is no distinction between Jew and Greek; for the same Lord is Lord of all, and is rich to all who call on him.
13 For, "Whoever will call on the name of the Lord will be saved."
Above, in verse 13, the Apostle Paul quotes Joel 2:32, which originally applied to Yahweh. Therefore, proponents of the doctrine that one must believe Jesus is God use this passage to essentially state that in verse 9, what one must confess is that "Jesus is Yahweh", and if they do not, they will not be saved.
In response, a Unitarian would say that here, the Apostle Paul teaches that Joel 2:32 has an additional application to Jesus, as He has been exalted by the Father to Lordship (Acts 2:36, 5:31, Ephesians 1:20-22, Philippians 2:9-11, etc.). The passage itself, however, clearly distinguishes between God and Jesus (Romans 10:9).
As is the case with each Old Testament passage which originally referred to Yahweh, and is applied in some way to Jesus by the New Testament authors, this passage never actually says that Jesus is Yahweh. Instead, passages about Yahweh can be said to be fulfilled in Jesus, because it is the consistent teaching of the New Testament that God was in Christ to a degree that is unparalleled. To this end, Scripture says that Jesus is the "image of God" (2 Corinthians 4:4, Colossians 1:13-15), the "express image of his person" (Hebrews 1:3), that "God was in Christ, reconciling the world unto himself" (2 Corinthians 5:19), and that "in him dwells all the fullness of deity bodily" (Colossians 2:9). This closeness is to the extent that Jesus can say, "He who has seen me has seen the Father" (John 14:9), and "He who sees me sees him who sent me" (John 12:45).
Therefore, texts which spoke of Yahweh doing something can be fulfilled in Jesus, because Jesus is God's agent and representative, through whom He works (John 5:19-20, 10:32, 10:37-38, 14:10-11). God can ordain an agent, and delegate whichever prerogatives or privileges which He sees fit to bestow upon Him. This does not take anything away from God, because His agent was established entirely by Him, and all honor given to the agent is ultimately to the glory of God (Philippians 2:11).
The two passages examined in this article do not teach that Jesus is God, or that one must believe that Jesus is God to be saved. And, far from teaching that one must believe that Jesus is God to be saved, the New Testament, when carefully examined, does not teach that Jesus is God at all.