You are more cowardly than the man who peeped out

Explanation

of those exceedingly cowardly. For there was a certain man so cowardly that, for fear of Heracles, he hid himself in a cave, and out of cowardice died there. Peeping out from the cave and seeing Heracles, he was turned to stone; and the stone, in human shape, with its head sticking out from the cave, remains even to this day.