In Ancient Greece, a polis was a unit of political organization which is usually translated as "city-state". It is the root of words of ours such as politics, police, policy and polity.
In the conception of politics held by the Ancient Greeks, the polis was supposed to provide a public space in which free men could speak words and act out deeds together, thus attaining glory and access to eternity through remembrance - but only within the limits set out by the constitution. Interestingly, it was common for the constitution of a polis to be drafted by a foreigner, because this was not considered to be among the political activities; it rather was like building an arena (in this case, of laws) in which politics would be conducted. Once this was accomplished, the serious business of the polis could begin. The polis was not these laws or the city itself, but rather the citizens within.
What these citizens aimed for was not utopia (Plato, who did seek utopia, wrote in explicit opposition to contemporary practice), or economic progress or equality, but rather the pursuit of individual excellence in word and deed; and this was only possible specifically without equality, because it was the labour of slaves which freed the ancients from necessity and allowed them to think about such abstract things as human excellence.
What these free men aimed for was to achieve immortality through their deeds. But this immortality could only be achieved through the continued survival of the polis and not in the unpredictable world outside; and the preservation of the polis within the laws set down by the original lawgivers was a sacred goal insofar as it seemed to promise the eternal continuance of this community, and hence the remembrance of the community's deeds.