A great comment from Alvin
First off I would like to state that the Apostle John when writing his Gospel made clear in his prolog that Jesus was Jehovah God. By introducing the Son as the Word (Logos) John 1:1 and in verse 18 No one has seen God at any time. The only begotten Son,[f] who is in the bosom of the Father, He has declared Him.
But I believe in the narrative the disciples and also the ones who believed in Jesus as the Christ did not understand that Jesus was God. They believed in the One God of the Old Testament, and that you could not look upon God and live. They did not understand that the One true God was standing before them and that He had laid aside His glory so they could look upon Him. I believe they believed in Jesus in the Messianic sense, that He was the son of Joseph, the King of Israel from the line of David the Son of God. That God had given Him what to say and when He spoke He was speaking as God representing God.
This is a Messianic description of Jesus
John 1:29 The next day John saw Jesus coming toward him, and said, “Behold! The Lamb of God who takes away the sin of the world! Psalm 53
John 1:34 And I have seen and testified that this is the Son of God.” This could be understood as the Son of God as coming from the line of David. Because God called David's son His own son, as a son of God. 1 Chronicles 28: 5 And of all my sons (for the LORD has given me many sons) He has chosen my son Solomon to sit on the throne of the kingdom of the LORD over Israel. 6 Now He said to me, ‘It is your son Solomon who shall build My house and My courts; for I have chosen him to be My son, and I will be his Father. 7 Moreover I will establish his kingdom forever,
John 1:37 The two disciples heard him speak, and they followed Jesus. 38 Then Jesus turned, and seeing them following, said to them, “What do you seek?”
They said to Him, “Rabbi” (which is to say, when translated, Teacher), “where are You staying?”
40 One of the two who heard John speak, and followed Him, was Andrew, Simon Peter’s brother. 41 He first found his own brother Simon, and said to him, “We have found the Messiah” (which is translated, the Christ).
45 Philip found Nathanael and said to him, “We have found Him of whom Moses in the law, and also the prophets, wrote—Jesus of Nazareth, the son of Joseph.”
49 Nathanael answered and said to Him, “Rabbi, You are the Son of God! You are the King of Israel!”
If His disciples new He was God why would they marvel that He would talk to a women? John 4:27 And at this point His disciples came, and they marveled that He talked with a woman; yet no one said, “What do You seek?” or, “Why are You talking with her?”
29 “Come, see a Man who told me all things that I ever did. Could this be the Christ?”
Rose notice in this following verse Jesus doesn't use scripture to prove His Deity but uses scripture to make the case for using Son of God in His humanity. His argument seems to be if Judges were called god's by God why do you want to stone Me for calling myself the Son of God?
John 10:31 Then the Jews took up stones again to stone Him. 32 Jesus answered them, “Many good works I have shown you from My Father. For which of those works do you stone Me?”
33 The Jews answered Him, saying, “For a good work we do not stone You, but for blasphemy, and because You, being a Man, make Yourself God.”
34 Jesus answered them, “Is it not written in your law, ‘I said, “You are gods”’?[c] 35 If He called them gods, to whom the word of God came (and the Scripture cannot be broken), 36 do you say of Him whom the Father sanctified and sent into the world, ‘You are blaspheming,’ because I said, ‘I am the Son of God’?
Psalm 82 6 I said, “You are gods,[b]
And all of you are children of the Most High.
7 But you shall die like men,
And fall like one of the princes.”
Why would the disciples be so concerned if they new Jesus was God?
John 11:8 The disciples said to Him, “Rabbi, lately the Jews sought to stone You, and are You going there again?”
Rose if Martha believed Jesus was God why did she say if you asked God He would give Him as if Jesus Himself wasn't God?
John 11: 21 Now Martha said to Jesus, “Lord, if You had been here, my brother would not have died. 22 But even now I know that whatever You ask of God, God will give You.”
11:39 Jesus said, “Take away the stone.”
Martha, the sister of him who was dead, said to Him, “Lord, by this time there is a stench, for he has been dead four days.”
40 Jesus said to her, “Did I not say to you that if you would believe you would see the glory of God?”
If they new God was standing right before them do you think they would have questioned His ability to raise a dead man that had been rotting four days?
Jesus meets them where they are, else believe Me for the sake of the works themselves.
John 14:7 “If you had known Me, you would have known My Father also; and from now on you know Him and have seen Him.”
8 Philip said to Him, “Lord, show us the Father, and it is sufficient for us.”
9 Jesus said to him, “Have I been with you so long, and yet you have not known Me, Philip? He who has seen Me has seen the Father; so how can you say, ‘Show us the Father’? 10 Do you not believe that I am in the Father, and the Father in Me? The words that I speak to you I do not speak on My own authority; but the Father who dwells in Me does the works. 11 Believe Me that I am in the Father and the Father in Me, or else believe Me for the sake of the works themselves.
Now we know? Do they?
John 16:29 His disciples said to Him, “See, now You are speaking plainly, and using no figure of speech! 30 Now we are sure that You know all things, and have no need that anyone should question You. By this we believe that You came forth from God.”
31 Jesus answered them, “Do you now believe?
John 20:28 And Thomas answered and said to Him, “My Lord and my God!”
29 Jesus said to him, “Thomas,[d] because you have seen Me, you have believed. Blessed are those who have not seen and yet have believed.”
Here a born again believer finally calls Jesus God!
I believe Son of God and Christ are interchangeable as Zane does.
John 9:34 They answered and said to him, “You were completely born in sins, and are you teaching us?” And they cast him out.
35 Jesus heard that they had cast him out; and when He had found him, He said to him, “Do you believe in the Son of God?”[a]
36 He answered and said, “Who is He, Lord, that I may believe in Him?”
37 And Jesus said to him, “You have both seen Him and it is He who is talking with you.”
38 Then he said, “Lord, I believe!” And he worshiped Him.
Rose to believe in the Son of God was to believe in the Christ the One who gives life! As in 1 John 5:1a Whoever believes that Jesus is the Christ is born of God.
1 John 5:4 For whatever is born of God overcomes the world. And this is the victory that has overcome the world—our[a] faith. 5 Who is he who overcomes the world, but he who believes that Jesus is the Son of God?
So in closing I believe that anyone can believe in Jesus for His promise of eternal life without having to believe that He is God just as the ones did in the narrative of John's Gospel. He said that His words were not His own but were from the Father and because of His miracles they believed Him.