A strange but curious question: if you had a time machine...

[Pyrrho]

The historical Jesus most likely existed.

I'm not a specialist on this but some members here will strongly disagree with you.

...

Yes, they will. First, there are no contemporary writings that mention Jesus. This is quite striking, considering his supposed significance. And contrasts greatly with people like Socrates, who existed hundreds of years earlier, about whom we have three contemporary accounts. One would think that if Jesus were anywhere near as important as he is purported to be, that someone would have written about him while he was alive. But we have absolutely nothing written about him during his supposed lifetime.

Second, the stories about Jesus get more detailed the further in time one gets from him historically. This is somewhat obscured by the fact that the Bible has the books NOT ordered chronologically from when they were written, but in an order that helps promote the religion by having more detailed accounts put first in the New Testament rather than having the earlier writings first. More details more removed from the time suggests that they are fiction rather than reports of actual events.

Third, the stories about Jesus resemble earlier stories about divine beings, which suggests that the stories are simply copies of old ideas rather than an attempt at actual history.

Fourth, the Bible books contradict each other on key points. For example, the gospels all tell us different stories of the resurrection. The best description of that bit that I have seen is an article entitled "The First Easter: Evidence for the Resurrection Evaluated" by John K. Naland in Free Inquiry, Vol. 8, No. 2, Spring 1988. But you can get an idea about this with a simple online search for:

• contradictions resurrection accounts

Fifth, individual books contradict themselves, by telling stories and then later telling us that they are false. (This, by the way, is mentioned by B.C. Johnson in The Atheist Debater's Handbook.) For example, in Luke 1:26-35, we have:

• 26 And in the sixth month the angel Gabriel was sent from God unto a city of Galilee, named Nazareth,
  
  27 To a virgin espoused to a man whose name was Joseph, of the house of David; and the virgin's name was Mary.
  
  28 And the angel came in unto her, and said, Hail, thou that art highly favoured, the Lord is with thee: blessed art thou among women.
  
  29 And when she saw him, she was troubled at his saying, and cast in her mind what manner of salutation this should be.
  
  30 And the angel said unto her, Fear not, Mary: for thou hast found favour with God.
  
  31 And, behold, thou shalt conceive in thy womb, and bring forth a son, and shalt call his name Jesus.
  
  32 He shall be great, and shall be called the Son of the Highest: and the Lord God shall give unto him the throne of his father David:
  
  33 And he shall reign over the house of Jacob for ever; and of his kingdom there shall be no end.
  
  34 Then said Mary unto the angel, How shall this be, seeing I know not a man?
  
  35 And the angel answered and said unto her, The Holy Ghost shall come upon thee, and the power of the Highest shall overshadow thee: therefore also that holy thing which shall be born of thee shall be called the Son of God.

But in Luke 2:41-50:

• 41 Now his parents went to Jerusalem every year at the feast of the passover.
  
  42 And when he was twelve years old, they went up to Jerusalem after the custom of the feast.
  
  43 And when they had fulfilled the days, as they returned, the child Jesus tarried behind in Jerusalem; and Joseph and his mother knew not of it.
  
  44 But they, supposing him to have been in the company, went a day's journey; and they sought him among their kinsfolk and acquaintance.
  
  45 And when they found him not, they turned back again to Jerusalem, seeking him.
  
  46 And it came to pass, that after three days they found him in the temple, sitting in the midst of the doctors, both hearing them, and asking them questions.
  
  47 And all that heard him were astonished at his understanding and answers.
  
  48 And when they saw him, they were amazed: and his mother said unto him, Son, why hast thou thus dealt with us? behold, thy father and I have sought thee sorrowing.
  
  49 And he said unto them, How is it that ye sought me? wist ye not that I must be about my Father's business?
  
  50 And they understood not the saying which he spake unto them.

Now, how is it that they did not understand what Jesus was saying there? There is no way one is going to forget an angel visiting you and telling you that your virgin fiancée has been impregnated by God, so you should go ahead and marry her anyway. So if this later story is true, the earlier one about the virgin birth is false. The story is not consistent with itself.

Sixth, the claims made in the stories are such that, were they true, they would certainly have been mentioned by historians of the time. For example, the idea of a star guiding the wise men from the east to a stable. Aside from the fact that a star cannot guide you to a specific stable (so it is nonsensical in itself), if there were some special astronomical event, the Romans and others would have commented on it. Yet there is no such record of any such thing by anyone else anywhere in the world. This is proof that the book is fiction, not anything real at all.

The upshot is, we have zero evidence that there was any guy named Jesus upon which the stories are based. Of course, there might possibly have been some individual who inspired the stories, but we have no reason to believe it, as there is no evidence for it.

Of course, many people do not like a conclusion that something is unknown, and so they will desperately cling to something, to pretend that they know what they do not know.

Frankly, though, it makes no difference whether there was some guy upon whom the stories are based, as the stories overall must be false anyway.