The application of the Christian teachings of natural law and revelation to ethical issues. It has largely been associated with the Roman Catholic Church as the infallible guide and interpreter of revelation and (sometimes) understood as casuistry in the pejorative sense of elaborate and petty legalisms. Moral theology can best be regarded, not as an attempt to provide detailed answers in advance, but as the provision of a cumulative wisdom derived from its sources which can be useful to Christians facing moral problems. These sources are Scripture, reason illuminated by faith, and the teaching of the church (specially as found in* and *), but the weight attached to these sources varies, the Catholic tradition putting more emphasis than the Protestant on the last.
Some Protestants have written works of moral theology, notably the Anglican* and the Puritan ,* while twentieth-century Anglicans in the Catholic tradition-such as K.E. Kirk,* R.C. Mortimer, and Herbert Waddams have sought to revive interest in the subject. In general, Protestant theologians use the term “Christian ethics,” which concerns itself largely with general principles, over against “moral theology,” which applies general principles to particular cases. The Protestant tradition, reacting against the danger of legalism in moral theology, stresses the individual and subjective aspects of the moral life-personal devotion and obedience to God's will.
The history of moral theology suggests there is a recurrent danger of a type of legalistic casuistry which is divorced from the wholeness of Christian living and which, at its worst, appears concerned to discover how much moral responsibility can be evaded. The connection of moral theology with the confessional and the inevitable links with canon law regulations tended to foster the legalistic and external aspects in the Roman tradition, but recent writing has shown a trend toward a wholeness of approach in moral theology involving the related subjects of ascetic, sacramental, and pastoral theology.