Archbishop Giampaolo Crepaldi, secretary of the Pontifical Council for Justice and Peace, has written a book entitled, "Catholics in Politics." The introduction by Stefano Fontana is available on Zenit. An excerpt:
The fundamental issue tackled by Most. Rev. Crepaldi's book (Catholics in Politics, A Handbook for the Recovery, Cantagalli, Siena 2010) is the status of politics, what politics is, and in doing so it assumes a metaphysical vision of politics, which serves as the epistemological basis for a theological foundation of politics. To paraphrase what Horrkheimer had to say in "Nostalgia of the totally other-than-self", and Joseph De Maistre even before him, politics is first of all and above all a theological issue. This is the book's main premise and on that basis it challenges Catholics in politics. Opening up before us on the basis of this approach to things is a complete series of fundamental questions.
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The subject of the book, therefore, is whether the city of man can be suitably constituted without reference to the city of God. It is a matter of the autonomy of the temporal with respect to the spiritual, of nature with respect to race, of politics with respect to religion. A fundamental theme for all times, but especially for ours, which seem to even have lost the selfsame sense of the problem at hand, to say nothing of its solutions. St. Augustine pondered the causes behind the downfall of the Roman empire. He defended the Christians against those who accused them of being the main cause and called the pagans into the picture saying the empire had fallen due to the vices that had replaced the traditional virtues. But this means the virtues existed even before Christianity. Gilson notes in this regard: he specified this so people would not deceive themselves about the specific supernatural aim of the Christian virtues. The Christian virtues make Christians citizens of another city. But in so doing Christianity also releases all the constructive forces of temporal society and it is not necessary for the temporal sphere to refuse looking upon itself as a stage towards eternity. This is why I consider the more important phrase of Bishop Crepaldi's book to be the one on page 63; a phrase well worth the whole book: "When a Catholic in politics strives to clarify the problem of laicity for himself I think he should ask himself two questions: the first is if Christ is just useful for the building up of social togetherness in harmony with human dignity, or if He is indispensable. The second is if eternal life after material death has any relationship with the community organization of this life in society".