[27] Question 27. Why do they repute every wall immaculate and sacred, but the gates not so?
Solution. Is it (as Varro hath wrote) that the wall is to be accounted sacred, that they might defend it cheerfully and even lay down their lives for it? Upon this very account it appears that Romulus slew his brother, because he attempted to leap over a sacred and inaccessible place, and to render it transcendible and profane; but it could not possibly be that the gates should be kept sacred, through which they carried many things that necessity required, even dead corpses. When they built a city from the foundation, they marked out with a plough the place on which they intended to build it, yoking a bull and a cow together; but when they did set out the bounds of the walls, measuring the space of the gates, they lifted up the ploughshare and carried the plough over it, believing that all the ploughed part should be sacred and inviolable.