In the early years of the publication of Christianity Today, Carl Henry, serving then as editor, delineated five tenets on Christian social and political action. I think this is a sound and balanced approach:
1. The Bible is critically relevant to the whole of modern life and culture -- the socio-political arena included.
2. The institutional church has no mandate, jurisdiction or competence to endorse political legislation or military tactics or economic specifics in the name of Christ.
3. The institutional church is divinely obliged to proclaim God's entire revelation, including the standards or commandments by which men and nations are to be finally judged, and by which they ought now to live and maintain social stability.
4. The political achievement of a better society is the task of all citizens, and individual Christians ought to be politically engaged to the limit of their competence and opportunity.
5. The Bible limits the proper activity of both government and church for divinely stipulated objectives-- the former, the preservation of justice and order, and the latter, the moral-spiritual task of evangelizing the earth.
~ Carl F. H. Henry, Confessions of a Theologian, pp 270-71.