His Word is subject to interpretation, else there would be only one branch of Christianity and there would be no Jews.
At the time of Jesus and John, there was no "science" as we know it today. They had to frame their words in terms of the world as they knew it (as do we all).
Before I go on, are you a YEC?
150 years ago 'there was no "science" as we know it today' either!
"By their fruits you shall know them."
Can't you tell from my posts whether I'm a YEC or not?