The theology of the cross, that ‘thin tradition’ stretching back through Luther and Augustine and Paul to find its origins in the Hebrew Scriptures themselves, has often been counterposed to the thicker, yet equally long, tradition of mysticism. In recent years, however, distinctions between these traditions have been expressed less categorically. It is now generally recognized that mysticism cannot be regarded as a single phenomenon. Rather, an understanding of diversity within the mystical tradition is foundational to an adequate appreciation of the richness, not only of mysticism, but of the theology of the cross as well. Ecumenical concerns have provided an incentive for discovering complexities in both traditions, and for breaking down the artificial barriers of long-held prejudices. This may make it possible to perceive ‘mystical theology in Martin Luther and evangelical theology in John of the Cross’.

The subtitle of my lecture suggests a theological sport called ‘Long Jump across Lessing's Gulf’ —jumping across the yawning gulf of historical criticism. However, it is a strange sport; no one has ever won. No one has ever succeeded in jumping across the gulf. Despite several run-ups I, too, have always failed. I've always ended up in the ditch. There, I discovered something important; the ditch is filled with water and it's fun to swim in it. Today, I would like to invite you to do just this; to jump into the ditch, into Lessing's gulf, to plunge into the cold water with me. It may not be as long jumpers but as swimmers that we arrive at the other side — even though we will then need a helping hand to reach dry land.

It has often been remarked by Schleiermacher's critics that his surprisingly high Christology is an awkward interlude in what may otherwise be described as a transcendental philosophy of religion. Schleiermacher's brief intoxication with Romanticism as evidenced in the Speeches, the undeniable influence of Schelling and Spinoza upon his early intellectual development, and the fact that The Christian Faith begins with a general description of the God-consciousness, all contribute to the suspicion that The Christian Faith is primarily an attempt to harmonize Christianity with the prevailing cultural thought forms of the day. This is, for instance, the way that Barth describes Schleiermacher's project: first and foremost, he understands it as an enterprise in apologetics.

The concept of unio mystica stands out of the more distinctive aspects of H.R. Mackintosh's theological work. Generally regarded as one of the leading English-speaking theologians of the first third of this century, Mackintosh and his innovative insights have since fallen into comparative neglect. Interestingly, the concept of the unio mystica seldom appeared as a theme on its own, apart from his programmatic article ‘The Unio Mystica as a Theological Conception’ (1909). Rather it served as a leitmotif which recurred at important points in his christology and soteriology. This essay will survey the meaning and importance Mackintosh gave to the unio mystica, and the various ways the concept functioned in his theology. Hence the first part will reconstruct his understanding of union with Christ, while the second part will examine three main applications of the concept: participatory christology, justification, and the Christian life. We will also explore some of the potential the concept may have for contemporary theology in a few concluding remarks.