The Bible can’t be taken as the inspired word of God because it contains myths.
Religious traditions in general are mythological.
The Bible can’t be “proven” scientifically or historically – and is therefore mythological.
Myths are by nature fictional.
There’s no difference between the myths of God/Jesus and the myth of, for example, Santa Claus.
Clarify the word myth:
If the word myth refers to the traditional stories of a tribe or people group (such as ancient Israel or the early Christians), the accounts can certainly be true. Thus the label “myth” is no critique against the Bible. However, most lay people use the word myth to mean fiction or fable.
Ask discerning questions of the skeptic:
How much of the Bible have you read?
Where do you get your information about the Bible?
Which parts of the Bible are mythological? The Bible is comprised of 66 different books written in a variety of genres ranging from historical narrative to poetry. Surely it’s an exaggeration to say they’re all mythological.
Do you think Jesus is a myth? Why?
The manuscripts of the New Testament are among the earliest and most numerous of any ancient documents, easily trumping the works of ancient writers such as Homer, Tacitus and Julius Caesar (see Eddy/Boyd).
Most of the creators of this supposed myth (fiction) were martyred or severely persecuted for their beliefs. But why? People will die for causes they believe are true – but not for a known falsehood. Imagine a person who fabricates a sighting of the Loch Ness monster, the Abominable Snowman or Bigfoot – or creates a false story about an alien abduction – and consequently is threatened with death. Will that person maintain their story and die? Probably not. The early Christians were willing to die only because they believed their accounts of Jesus were true.
The difference between Santa Claus and Jesus
Historians are nearly unanimous in believing that Jesus existed. No one is claiming that Santa Claus actually exists.
The existence of some myths doesn’t mean everything is a myth. Think of it: Santa Claus is a myth. Therefore Jesus is a myth. That’s not much of an argument.
Ask the person if they’d be willing to read the accounts of Jesus with you and talk about them.