The prevailing wisdom today is that religion has no place in the public square because somehow, in some way, by some miracle, secularism guarantees an unbiased neutrality while religion is laced with bias and irrationality. People can, therefore, be free to be what they like in their private prayers, but must not impose their views - or even air them - in the public arena. There is nothing particularly new about such an approach. Lord Melbourne, in opposing William Wilberforce's campaign against the slave trade, lamented: “Things have come to a pretty pass when religion is allowed to invade public life.” Presumably, this would have meant that if faith in Christ were not allowed to show itself in public, then the abolition of the slave trade would have lost its drive and momentum.
The result is not neutrality, tolerance, and harmony. In the above example, the result would be the victory of the slave trade. In our day, it might mean the victory of demands for the recognition of homosexual relations or free abortion. The truth is that every opinion in the public arena has a foundation in one kind of worldview or another. If Christians cannot express the Christian view, the result will not be impartiality but the triumph of another, unchristian, worldview.
Faith has a place in the public square, even in days when paganism prevails: Joseph worked under Pharaoh who thought that he was the incarnation of the sun god (Gen. 41:37-45); Daniel became the leading president under
King Darius of Persia (Dan. 6:1-3, 28); while Nehemiah made use of his position as cupbearer under King Artaxerxes to become the governor of Judah, and so rebuild the wall around Jerusalem (Neh. 2:1-8). Christians may not always command a majority behind them, but they have a legitimate place in public affairs, not just in terms of living Christianly but to put forward Christian views. A society which builds itself up on a foundation of secularism will find that it is only another form of idolatry. It is righteousness, not sin, which exalts a nation (Prov. 14:34).
To return to Wilberforce, he did not regard Christianity as essentially political but considered that it had wonderful political benefits. He often cited Colossians 3:2, “Set your affections on things above.” The paradox is that only the heavenly minded can be of much earthly use.