Scottish-born Reformed theologian, John Murray (1898-1975), who taught at Princeton Seminary and later on helped to found Westminster Seminary was not quiet about the roll of the church as it relates to politics.
When laws are proposed or enacted that are contrary to the Word of God, it is the duty of the church in proclamation and in official pronouncement to oppose and condemn them. . . . It is misconception of what is involved in the proclamation of the whole counsel of God to suppose or plead that the church has no concern with the political sphere. The church is concerned with every sphere and is obligated to proclaim and inculcate the revealed will of God as it bears upon every department of life…
…To the church is committed the task of proclaiming the whole counsel of God and, therefore, the counsel of God as it bears upon the responsibility of all persons and institutions. While the church is not to discharge the functions of other institutions such as the state and the family, nevertheless it is charged to define what the functions of these institutions are. . . . To put the matter bluntly, the church is not to engage in politics. Its members must do so, but only in their capacity as citizens of the state, not as members of the church. (pg. 241, 255)
HT: Justin Taylor