One of the chief points of differentiation between theological ethics in the evangelical tradition and in the mainline tradition is the locus of authority. For evangelicals the chief—even the exclusive—source of authority is sola Scriptura (Scripture alone). Despite authoring numerous confessions and catechisms, all viewed as penultimate, Scripture remains the centerpiece of evangelical theological ethics. Beliefs and practices require some biblical warrant in order to be binding upon the conscience of the individual Christian.

In contrast, the mainline Protestant notion of authority developed quite differently. Mainline Protestants came to believe that an ethics derived exclusively from Scripture and experience would necessarily be blind to the...