" 'I am content to stay with mystery.' This was the response of the guide taking tourists around the great prehistoric chamber tomb of Knowth in the Boyne valley in Ireland when they asked him about its purpose, and the meanings of the dynamic abstract designs which decorate its huge rock slabs. Of course we will go on asking questions, but I hope that I will also be content to stay with that answer, and I shall be happy to accept that in the end the thought patterns of these ancient Celtic people and the way in which they saw their universe will continue to elude me, in spite of all the advances of academic scholarship. . . . Pause — take time — do not fill up all the spaces.

"Everything in this retreat so far has brought me to this point: silence, listening, gazing, taking time, attentiveness, wonder. Those huge Irish prehistoric tombs have given me the natural starting point for today's theme of mystery, for the Celtic world is at once familiar but also ultimately unknown. In recent years I am so grateful that I have come to discover the Celtic tradition, above all in Wales and Ireland where I have not only traveled widely but also tried to read widely. Yet I feel in the end I have encountered a people whose imagination eludes me and will continue to elude me. As Celtic interest widens and increasing numbers of people become enthusiasts for all things Celtic, I think we should recall the words of a man who was arguably the most distinguished Welsh poet of our day, R. S. Thomas:

"You can come in
You can come a long way . . .
But you won't be inside.

"So I try to walk in reverence, taking off my shoes, remembering that this is holy ground, and having to accept that there is much that I shall never fully know and that may in the end be the most important gift of the Celts."