Sidney Nolan's Inferno is a grand frieze alluding to Dante's Divine Comedy

Sidney Nolan was given to making grand statements on the nature of humanity through his art - a commentary on the human condition viewed within a historic context. Themes in his oeuvre ranged from Ned Kelly as a rebel and fugitive from justice, the heroic Anzacs senselessly dying at Gallipoli, through to Greek mythology touching on eternal themes of human existence.

In 1966, aged 49, Nolan painted a grand nine-panel frieze simply titled Inferno, a painting that was valued by the artist, included by him in his early retrospectives, and it was retained in the artist's collection. Following Nolan's death in 1992, it has been toured by the artist's estate to various venues including the Art Gallery of South Australia and it now forms the focal point of an intriguing exhibition at the Canberra Museum and Gallery (CMAG).

The title, Inferno, alludes to the first part of the great love poem of the Italian Renaissance, Dante's Divine Comedy, where the poet physically and metaphysically is guided from hell to purgatory and finally to paradise to catch a glimpse of his beloved Beatrice. Allegorically, it also represents the passage of the soul, after death, to God.

CMAG director Dr Sarah Schmidt has cleverly created for this painting a niche within Nolan's other work held in the museum's Commonwealth Nolan Collection - including the magnificent drawings from For the term of his natural life series, a screenprint from the Inferno series and other work - to make the point that the huge painting was Nolan's manifesto on human suffering through the ages and that it is equally relevant today as it was when Nolan made it. Through detailed wall texts, Schmidt has brought together different interpretations of the painting made by scholars over the years and comments on some of the painting's possible sources.

How are we to respond today to Nolan's Inferno? Its dimensions are mesmerising so that you cannot capture the whole canvas in a single glance and yet it stubbornly refuses to break down into segments. It is a monumental epic, a statement about pain and the inhumanity that people are capable of inflicting on other people - a statement that has no beginning or end. Like Dante, Nolan loaded his hell with victims of a personal vendetta and noted at the time that he could "use inside Heide as hell". A few years before painting the Inferno, Nolan commented in a letter to Albert Tucker on the atmosphere at Heide and the "demonic effect of the Reeds". However, the painting, as in much of Nolan's best work, goes considerably beyond the local and particular to embrace the general and universal.

Nolan felt that he achieved something significant in the big painting for in the following year, 1967, he made nine colour screenprints simply titled Inferno with Chris Prater, the genius printer in London who revolutionised the art form. One of these, Inferno viii, is included in the present exhibition.

Nolan was ridiculously prolific with an estimated 35,000 paintings to his credit, not to mention the many thousands of drawings, prints, stage set designs and three-dimensional works. Many of his works are best forgotten and when I confronted him about the sheer volume of his production, his response was laconic, "Posterity is a bitch, she'll take what she wants". The Inferno painting is big, problematic, challenging, but very memorable, and I suspect it will remain on Nolan's shortlist of major works well into the future.