In effect is Schillebeeckx's general introduction to theology. Its fifteen chapters were originally published separately between 1954 and 1962, but the thematic collection offers a vivid picture of the theological renewal in the wake of World War II. Schillebeeckx's erudition and broad scholarly orientation are clearly demonstrated in this volume. Throughout there are pointers to the (at that time new) ecumenical approach to Scripture and tradition. The problem concerning the function of the scholastic tradition is highlighted. Although Schillebeeckx draws extensively on Thomas Aquinas's thinking, this early work already shows that he is not a (neo)Thomist in the narrow sense of the word. Unlike the single Dutch volume, the English version was published in two volumes. In the , however, here they are published together in the sequence that the author envisaged.