Saying something never happened because it was not in the Bible denies the humanity of the people in it. It also at times defies common sense. These were real people who lived and interacted with one another. They shared a common experience that no one can fully comprehend unless they lived it.
Then you open up truth to any source or any group who claims to have truth. It is easy to say, "I had a revelation and God said ______________". This is what the tv evangelists and the health/wealth preachers are ridiculed for.
A lot of false teachers are in the world today.
Without a standard of truth by which to measure their claims how do you know they are right.....or wrong?
Islam claims it is the truth but we deny it because it doesn't square away with the Bible.
Mormons claim the Book of Mormon is truth, yet we deny it because it doesn't square away with the Bible.
Mormons also claim Jesus visited the Indians of North America....do you believe them? If not, why? What source did you use to evaluate their claim?
This same line of reasoning can be said about any other group outside of Christianity.
If the Bible is not the standard, then what is?