John 7:27

When Christ cometh, no man knoweth whence he is.

There was an expectation, probably due to Daniel 7:13, that the Messiah would suddenly appear in Jerusalem without any one knowing whence he came. These men, therefore, reason that this cannot be the Christ because they knew from whence he was. They knew that he came from Galilee and probably that his early home was at Nazareth, but were ignorant of the fact that Bethlehem was his birthplace. Nor did they know of his heavenly origin, so that it was literally true that the Christ was before them and no man knew whence he came. It might be well to add that the Jewish tradition held that Bethlehem would be the Messiah's birthplace, but he would be caught away by spirits and tempests and lie hidden until he should miraculously appear to enter upon his mission.