The following outline is provided as an overview of and topical guide to Christian theology: Christian theology is the study of Christian belief and practice. Such study concentrates primarily upon the texts of the Old Testament and the New Testament as well as on Christian tradition. Christian theologians use biblical exegesis, rational analysis and argument. Theology might be undertaken to help the theologian better understand Christian tenets; to make comparisons between Christianity and other traditions; to defend Christianity against objections and criticism; to facilitate reforms in the Christian church and to assist in the propagation of Christianity.