In the mid seventh century a young man was sitting on a hillside in Northumbria late at night, having taken some work tending a flock of sheep. As he sat watching the stars glittering over the faraway horizon, a faint sound of song seemed to drift across the fields, panging him with an aching beauty. Suddenly, beams of light streamed out of the sky and to his amazement he saw angelic figures swimming down as if out of nowhere, flocking towards the monastery. Out of a haze of light and choral song they seemed to bear away a human figure before disappearing into the night, leaving the young man alone with the bleating sheep.

The next day he left the sheep and went to the monastery at Melrose, where he found that the departed figure was St Aidan, an Irish missionary who had brought Christianity to Northumbria, and he was so moved he sought to join the monastery himself as a monk. There the young man went on to live a life of remarkable devotion, and later stories recount many miracles that surrounded his time as bishop. He predicted the future, knew faraway events as they happened, angels provided him with food on long journeys, eagles brought him fish, otters swam out of the sea and warmed and washed his feet after all-night vigils up to his waist in the freezing water. But all this was still not enough. From the windswept coast of Northumbria he looked out into the North Sea and began to plan his retreat to the remote bird-flocked islands out on the distant waters where he could be alone with God.