THE Viking runes are a spidery scrawl, a eulogy to a long-dead king at the entrance to a cave once inhabited by an early Christian saint.

Along the shore, a painting of another venerable figure adorns a large rock. The jolly character in maroon and saffron robes is Dusum Khenpa, the first Karmapa, disciple of Gampopa and main guru and Karma Kagyu Lineage holder. In other words, a Buddhist saint.

The Vikings used knives to carve the name of their king above the cave on Holy Island, off Arran. Dechi Wangmo, a Buddhist from London, used acrylic marine paint designed for oil rigs to portray her spiritual guide. ''It is supposed to resist the elements better than ordinary paint,'' she explains. ''We'll see. Time will tell.''

The technology may have moved on a bit, but the message is the same. For centuries the isle has been a refuge, either physical or spiritual, and with its purchase by a Tibetan Buddhist Trust in 1993, it has come full circle. More than a thousand years after Saint Molias lived in the cave by the western shore, the followers of Buddha are planning to build a larger and rather more sophisticated retreat on the southern slopes.

Where the Christian missionary contented himself with an open fireplace, spring water, and a table and seats of stone, the new generation of holy men (and women) will be able to meditate in hi-tech glass-fronted cells equipped with showers and underfloor heating systems, powered largely by the sun and wind.

The #8m project envisages a self-sustaining and non-polluting complex for more than 100 residents, sunken and layered discreetly into a hillside to minimise the environmental impact. The award-winning design by a London-based architect is thus ecologically sound, politically correct, and spiritually pure. It will also have a nice view of the sea.

Nobody seems quite sure when the centre will get off the ground, or rather into it, but then time is a relative concept on Holy Island. When you believe in reincarnation, there isn't much pressure to hurry.

Dechi the rock-artist, who serves as a caretaker on the island, explains that the Samye Ling Tibetan centre in the Borders hasn't actually raised the money for the complex yet. ''It's a long-term project,'' she says. ''We want to do the best we can, so we would rather take time than rush at it. When the time is right, it will happen.''

Plans have been submitted to North Ayrshire Council, and if they are approved it is hoped that work might begin on the first eight individual units in the spring. For the moment, the site is marked by a straggle of wooden posts on the southern flank of Mullach Mor (big top), the rounded 1000ft that dominates the island. On a ridge, the slender figure of an anenometer tests the wind for power-generating capacity.

The only building in the patchwork of heather and rough grasses is a log cabin, completed a couple of years ago for occasional visits by Lama Yeshe Losal, the abbot and retreat master of Samye Ling. It occupies the highest position on the site, above the planned separate male and female retreat cells.

Presently this little haven of tranquillity is shared by about a dozen residents, a similar number of volunteers renovating a farmhouse, a small herd of Eriskay ponies that has just produced four foals, three flocks of Soay sheep which are one of only three breeds in the world which don't have to be sheared, and a fluctuating number of feral goats.

Separating the sheep from the goats, a problem since Biblical times, is particularly tricky on Holy Island because Soay sheep and the local Sanaan goats look remarkably alike. They all have horns and a generally wild appearance.

The only discordant note in all this harmony of man and beast is the chomping of rabbits in gardens and young woodland where 27,000 trees have been recently planted. Dealing with them is a problem for vegetarians sworn to respect the sanctity of all life.

Renchen, a Buddhist from Wales, explains the difficulty: ''We thought of hiring a man with a ferret to chase them away from the planted areas, but there is no guarantee the ferret wouldn't kill them. Then we thought we might smoke them out, but we couldn't get the smoke to go down the holes.''

The human population is divided between two former lighthouse keepers' houses at the south end of the island, and the farmhouse at the north end. They are connected by a grassy path that meanders for a couple of miles through bracken along the sheltered western shore, beneath the crags of Mullach Mor where tufts of rare Rock whitebeam flash silver in the sun.

Strolling along this path on a warm summer's day, lulled by the lapping of waves on the shore, it is easy to understand why the island has long been a place of pilgrimage and refuge. The sense of peace is almost tangible.

It is also a good place to practice your golf swing, according to Dechi. She recalls a visiting monk who was fond of the game, and brought his clubs with him. In the absence of a golf course, or anything remotely resembling a flat, open area, he amused himself by hitting balls into the sea. As long as his supply of balls lasted, he found this satisfying.

You don't have to be a spiritual person, or a frazzled bundle of neuroses, to benefit from Holy Island, Dechi says. But bearing in mind the community's motto helps. It is: ''Inner peace leads to world peace.''

Martina seems to have achieved the first part. She is a social worker from Germany, who is paying #21 a day for room and board for a week in one of the lighthouse cottages. A tall, quiet woman with a gentle smile, she spends her time walking, reading, and meditating. She says she is here to ''come back to myself'', and it looks like it has been a happy reunion.

Big Rob Urie is too busy sawing, hammering, and knocking holes in walls to contemplate eternal verities at the moment. An Australian who lives on a farm in France, he is on the island for 10 days as a volunteer worker, helping to renovate the farmhouse as the nucleus of a planned inter-faith centre for peace and reconciliation.

He is not a Buddhist with a capital B, he says. In fact he is not even a buddhist with a small b, although he is interested in the faith which he considers among the simplest and clearest of spiritual creeds. ''It's this atmosphere of working together that I like,'' he says. ''There's lots of positive energy.''

He is surrounded by men in women in dusty shorts, sweatshirts, and wellie boots, paying #8 a day for food and the privilege of gutting the old house and creating something they all believe in.

Renchen's speciality is dry-stone walls. ''It's good to feel you're doing something that will last, like planting trees and building stone walls. It's better than making cars or washing machines that will fall apart in a few years. And I like the idea of an inter-faith centre. When you're building a wall, it doesn't matter if you're a Christian or a Buddhist.''

The ethos of the place is summed up by a sign above an old wooden door. It says: ''commit random acts of kindness.'' Outside, brightly-coloured prayer flags flutter in the wind. Buddhists believe that the prayers written on them are carried by the breeze.

Like the retreat complex at the south end, the inter-faith centre is designed to be built in stages as resources become available. Here the aim is to provide 45 bedrooms and meeting facilities in a more traditional Scottish farmhouse style. Nicholas Jennings, the director of the development, agrees that Buddhist philosophy helps instil patience in such endeavours. ''We take the long view,'' he says.

A start has been made, however. Day visitors from Arran are greeted at the north end slipway by a painted board depicting scenes of the island, a helpful map, and the legend: ''May all beings be happy and create the causes of happiness.'' Beyond it, a white post in a circle of stones carries the message ''May peace prevail on earth'' in English, Gaelic, and Tibetan. Visitors also get a mug of tea, a chat with one of the residents, and the opportunity to sponsor a prayer flag for #1.50.

The inner sanctum of the community is the shrine room near the lighthouse. This is where devotees gather at least twice a day for prayer ceremonies, in which mantras are chanted to the rhythmic beating of small drums, the tapping of cymbals, and the tinkling of a bell.

Formerly the engine room, housing massive steam compression chambers for the foghorn, it is now adorned with prayer tables and an altar of Buddhas surrounded by offerings of flowers, candles, incense sticks and saffron water. After dusk, the ancient Tibetan chants float out of the open door to where moonlight shimmers on dark water.

Along the path, the image of Dusum Khenpa smiles benevolently from his rock towards the hills of Arran. So far the marine paint has done its job well, resisting the wind and salt spray. When the guru's features eventually fade, maybe Dechi will come back to repair her handiwork. In another lifetime.