Ancient scepticism was frankly opposed to religious belief.
But more important was the influence of philosophy, which led soon enough to a general scepticism among the upper classes.
But scepticism of this kind was not universal.
Like Socrates, he was not a philosopher, and did not pretend to be one; but, as the reasoned scepticism of Socrates cleared the way for the philosophy of Plato, so did Xenophanes's "abnormis sapientia" for the philosophy of Parmenides.
This scepticism took form in the school, most active between 1860 and 1880, known as the school of "Expectant Medicine."