"Systematic theology is beneficial as an extension of the teaching function of the churches, for the orderly and integrated formulation of biblical truths, for the undergirding of the preaching of preachers and lay Christians, for the defense of gospel truth against error that has invaded the church, for the legitimation of the gospel before philosophy and culture, as the foundation for Christian personal and social ethics, and for more effective universal propagation of the gospel and interaction with adherents of non-Christian religions."
—James Leo Garrett Jr., “Why Systematic Theology?,” CTR 3, no. 2 (1989): 281.