In the summer of 2019, Alistair Moffat set off on a long journey back into the past. Once the marquees from the Borders Book Festival had come down in the shadow of Melrose Abbey, he drove across Scotland into a sacred landscape of a very different sort.

In the 6th century the Word of God had sailed north from Ireland. Inspired by groups of eastern ascetics known as the Desert Fathers, Irish missionaries steered their curraghs to remote Hebridean islands and headlands. Surrounded by the wastes of the sea, they sought solitude, built monasteries and hermitages where they could pray, fast and seek to move closer to understanding the mind of God. Columba is the most famous of these hardy, leathery old saints, but many others set a course for sanctity in the Hebrides.

Alistair Moffat set off on a sea journey to Eileach an Naoimh, the Rock of the Saint, an uninhabited island in the mouth of the Firth of Lorne to discover more about St Brendan. From there he went to the overrun island of Iona, then to Lismore, the Great Garden, the Edenic centre of the parish of St Moluag, and finally to remote Applecross to walk in the footsteps of St Maelrubha.

It turned out to be a voyage of discovery in every sense.