...there is nothing particularly odd about a political philosopher being concerned with the question: how can we construct a community within which all persons can flourish? That's (one way to take) one of the central questions of political philosophy. However, defining Christianity as centrally concerned with the construction of community is not, to my mind, an obvious move. (Love, yes; the nature of community, no.) What's striking about the thesis, besides the cast of Rawls' mind and the glimpses of his twenty-odd year old self, is not how Christian his later work was (it isn't), but how very Rawlsian his take on Christianity is.
Further thoughts from Ezra Klein.