Mark Brumley – Catholic Answers Article –
The Catholic Church has a “conservative” attitude toward fundamental human institutions, values, and ways of behaving—to human dignity, marriage and family, social life, and government, for example. The Church is rightly said to be “conservative” in its defense of these basic human realities because it wants to conserve them.
At the same time, Catholic social teaching is an aspect of the gospel of Jesus Christ. The gospel involves radical conversion and liberation from sin. All is not right with man. Sin deeply affects human life and social institutions. If “liberal” is a word used to refer to someone who favors change in order to “liberate” people from social evils, then we can say there is a deeply “liberal” dimension to Catholic social teaching.
And, of course, we can think of a “moderate” as one who stands between extremes. Catholic social teaching moderates between an inappropriate conservatism, which holds on to attitudes, values, ways of acting, and institutions that ought to change, and inappropriate liberalism, which doesn’t promote genuine liberation but undermines or outright attacks things that ought not to change.