Here are the 3 questions that will be addressed:
Did the Biblical writers believe Jesus was God?
Did other people of the day believed Jesus claimed to be God?
Is it necessary Jesus was God?
Let’s initially look at whether the writers of the New Testament believed if Jesus was God or not. Paul in Philippians gives the incarnate description of Jesus coming into human form, but does not stop there. He capitalizes this idea with verse 11 stating “Jesus Christ is Lord”
“who, though he was in the form of God, did not count equality with God a thing to be grasped, but emptied himself, by taking the form of a servant, being born in the likeness of men. And being found in human form, he humbled himself by becoming obedient to the point of death, even death on a cross. Therefore God has highly exalted him and bestowed on him the name that is above every name, so that at the name of Jesus every knee should bow, in heaven and on earth and under the earth, and every tongue confess that Jesus Christ is Lord, to the glory of God the Father.”
(Philippians 2:6-11 ESV)
Also, in Matthew 9:2, Jesus tells the paralytic to get up and walk, his sins are forgiven. Matthew obviously sees Jesus as God here in that he mentions Jesus said “Take heart, my son; your sins are forgiven.” Which only God can do, see Mark 2:7. Secondly Matthew notes the proof or evidence. Anyone can walk into somewhere and claim their sins were forgiven, but only Jesus as God incarnate would have the power to make the life long paralytic walk again. Thus by enabling the man to walk through His power, Matthew is recording that Jesus would also have the ability to forgive sins.
Mohammed, Buhdda, and all the other great teachers could have said thought provoking claims. But none had the ability to forgive sin as Jesus did. This separates Jesus from all the other teachers there have ever been.
Next, let’s look at whether other people thought Jesus claimed to be God. Not only should we expect that the followers of Jesus believed his claim to be the messiah, but others should have taken note too. Josephus, a non-Christian first century historian said:
Antiquities 20.9.1 But the younger Ananus who, as we said, received the high priesthood, was of a bold disposition and exceptionally daring; he followed the party of the Sadducees, who are severe in judgment above all the Jews, as we have already shown. As therefore Ananus was of such a disposition, he thought he had now a good opportunity, as Festus was now dead, and Albinus was still on the road; so he assembled a council of judges, and brought before it the brother of Jesus the so-called Christ, whose name was James, together with some others, and having accused them as law-breakers, he delivered them over to be stoned.
Antiquities 18.3.3 Now there was about this time Jesus, a wise man, if it be lawful to call him a man, for he was a doer of wonderful works, a teacher of such men as receive the truth with pleasure. He drew over to him both many of the Jews, and many of the Gentiles. He was the Christ, and when Pilate, at the suggestion of the principal men among us, had condemned him to the cross, those that loved him at the first did not forsake him; for he appeared to them alive again the third day; as the divine prophets had foretold these and ten thousand other wonderful things concerning him. And the tribe of Christians so named from him are not extinct at this day.
Also, “Josephus, Tacitus, Suetonius, Pliney the Younger, Thallus, Celsus, Lucian of Samosata, Mara bar Serapion, and certain Jewish rabbinic traditions all contain some references to Jesus and/or the early Christian movement.” See The Jesus Legend by Paul Rhodes Eddy and Gregory Boyd
Lastly, does Jesus need to be God? Why can’t he be a good moral teacher, or a very wise person?
“And if Christ has not been raised, then our preaching is in vain and your faith is in vain. We are even found to be misrepresenting God, because we testified about God that he raised Christ, whom he did not raise if it is true that the dead are not raised. For if the dead are not raised, not even Christ has been raised. And if Christ has not been raised, your faith is futile and you are still in your sins. Then those also who have fallen asleep in Christ have perished. If in Christ we have hope in this life only, we are of all people most to be pitied.”
(1 Corinthians 15:14-19 ESV)
Paul says in his letter to the Corinthians that our faith depends on Christ being God, being raised from the dead. That if Christ has not raised “you are still in your sins”. We have no hope other than that Christ is God as He claimed to be. He must be God if we are to have salvation in God. Otherwise our sin leaves us separate from God, but Jesus has secured our eternal redemption (Hebrews 9:12)