In many ways John Bellany has always faced east – to the sea, during his childhood in the East Lothian fishing village of Port Seton; to the Low Countries and Germany, where as an art student he found inspiration in the work of Rubens, Rembrandt, Max Beckmann and Otto Dix; even to China, which he visited in 2003 and where he painted The Bundt Shanghai, a colourful scene of the city's famous waterway.

It sits in the room which closes this overdue survey of his rich, 50-year career, a huge block of orange-red dominating the painting's upper-right quadrant and looking for all the world like a vast, Impressionist sun rising in the sky.

Or is it one that's setting? Bellany, whose health problems have been well documented, is certainly now facing the coming twilight of his own life. He turned 70 in June, so this exhibition is both a double birthday present – to him and from him – and a career-closing retrospective.

Loading article content

Accordingly it runs chronologically, from his student works in Edinburgh and London in the early-to-mid-1960s through the powerful triptychs of the 1970s, to the wild work of the bleak, sick, boozy 1980s. From there it travels into the 1990s and beyond when, with a new liver and a new hold on life, he turned again to face the men and boats of his Scottish childhood and also the hills around Sipulicchia, his newly purchased Tuscan retreat. These last are the most placid of the paintings on display, untroubled by puzzling metaphor or by the coded symbolism of fish, monkeys, sea-birds and shrouds so often found in Bellany's work.

Mostly the artist's gaze falls on himself, his wife and muse Helen, and on what he would call "his people": the gnarled, sea-faring, God-fearing members of Scotland's fishing communities, both alive and dead.

We see them in one of the earliest works, 1962's The Boat Builders, and in the triptych Allegory from 1964, which was inspired by a Saturday job gutting fish at home in Port Seton. We see them again in The Box Meeting, Cockenzie, Bellany's hymning of a local tradition in which the deeds to the local boats are put in a box, paraded through the town and then blessed. It's about as close to a pagan ritual as you can get in the Kirk and in case anyone missed the point, Bellany based his painting of the ceremony on a copy of The Feast Of The Gods by Renaissance master Giovanni Bellini. Four decades on, he painted The Eyemouth Disaster, a commemoration in green, yellow and blood red of "Black Friday", the Great Storm of October 1881 which killed 189 men from the fishing communities of south-east Scotland.

Drawings and paintings of Helen, whom Bellany married, divorced and then re-married after the death of his second wife, are given a section in their own right, while the stark self-portraits he made after his liver transplant in 1988 have a wall to themselves. Featuring scars, tubes, stitches and more, they're among the most unflinching studies here.

Bellany's habit of painting a birthday self-portrait every year is a godsend for the curators, too – three are included, one from this year and two from the 1970s which, though painted just four years apart, show a radical change in style. The first, from 1972, is precise, the second more aggressive and gestural, a foretaste of the paintings Bellany made in the early 1980s and which are contained in a room titled Inner Turmoil And "Wild" Painting.

Bellany is not untravelled, however, and some of the most striking paintings are the results of his forays beyond these shores. In East Germany in 1967, for instance, he was taken to the former concentration camp at Buchenwald and moved by the experience to paint the massive pair Pourquoi? and Pourquoi? II. Both show three monumental figures, prisoners presumably. In the second work the trio hang crucified over skeins of barbed wire; in the first, they stand on a carpet of skulls against what looks like part of the right angle of a Swastika (though the curatorial notes prefer a cross). One figure has a bandaged head, one has stumps for arms.

Elsewhere there are paintings inspired by more recent visits to eastern Europe (notably Madonna Of The Dustbins, a rare moment of something approaching humour in Bellany's titles, though the subject is serious enough), by his time spent in Australia in the early 1980s, and by a trip he made to Mexico in the mid-1990s.

Mexican cultural traditions, steeped as they are in death, colour and riot, clearly appealed to him and in On Lake Patzcuaro we see how he incorporates them into his own Protestant, north European world-view. It's notable, by the way, that Bellany visited the lake on the Day of the Dead, the famous Mexican festival in which people pray for the souls of dead relatives: since the late 1970s, his canvases had often incorporated side-frames featuring ghostly ancestral figures. Indeed two of the most moving paintings in the exhibition (and featured side by side) are the 1985 pair Requiem For My Father – a melancholy self-portrait with the Bass Rock in the background – and Adieu, Requiem For Juliet, which shows his second wife lying in a sarcophagus with the artist half-disguised as a card-playing puffin. The ace of spades – the so-called "death card" – is the only one visible.

Across half a century of painting, style necessarily changes. But the narrative of John Bellany's life is so strong and his themes – the sea, mortality, time passing, guilt, pleasure, carnality – so constant that we can read the same story in almost every canvas. As chapter follows chapter, it never fails to enthral. This is a wonderful showing of a powerful body of important Scottish work.

John Bellany: A Passion For Life is at the Scottish National Gallery, Edinburgh until January 27.