Dutiful Christians might be surprised to find a mouse carved into one of the scenes depicting the Way of the Cross in Longford’s St Mel’s Cathedral, and even Australian visitors could hardly expect to see a kangaroo in London’s Westminster Abbey.

Sculptor Ken Thompson, however, can explain it all: these details are not whimsy, but connections, and they occur in the context of two of his recent commissions.

Of these, the largest and most demanding are the Stations of the Cross that are to be installed at the restored St Mel's Cathedral in Longford. The other is a tablet commemorating the 200th anniversary of the death of Admiral Arthur Phillip, Australia's first governor, which is to be unveiled by the duke of Edinburgh at Westminster Abbey tomorrow.

A small casement window brings the seaward light of Ballycotton on to the panels, which line Thompson’s workshop at Ballytrasna in Co Cork. “Relief carving depends for its success on the fall of light and shadow,” he says, as he switches on a spotlight to illuminate the first of the stations.

Unusually for Stations of the Cross, the text at the base of these panels is not descriptive, but allusive. "I like to let people work things out for themselves, and I thought, why not use this space not to say the obvious – that is contained in the imagery – but to put in inscriptions?"

Thompson chose two lines of scripture for each panel, cut them in his favoured classical Roman lettering and highlighted them in terracotta, one of the two colours used in the otherwise plain Bath stone.

The other colour is blue, which Thompson uses to give a background dimension that works almost like a shadow in itself, impelling the foreground figures into greater relief and enhancing the 24-carat gold leaf halos. These establish not only the central image of Christ but also those of his mother or a half-hidden disciple. The sequence makes an impressive narrative: a pillar conveys the passage of the doomed Christ through the city; an owl hovers above the head of St Veronica in an omen of death; and when Jesus is laid in the tomb, the panel is luminous, the lidded grave finished like a tablecloth.

Wrenching physicality

Every panel sketch is first prepared as a graph but this does not conceal the wrenching physicality of the crucifixion. Its impact is only mellowed subsequently by the gesture of the mother of Jesus as he is released from the cross, her cheek resting against his limp arm. This may be scripture, but even in its orthodoxy it is a human story, timeless and poignant.

Six of the 14 panels have already been dispatched to Longford, the half-ton slabs taken away by stonemasons Michael and Edward Sheedy of Midleton, Co Cork. The remainder, finished or unfinished, indicate that there is a kind of relativism at work in these depictions. That mouse, for example, is a reminder of a traditional belief that as a carpenter St Joseph made mouse-traps. The less benign legend has the mouse as the devil disguised, and Thompson manages to weave this reference into an almost textual example of sermons in stones. The blocks are sturdy, the carving deep and strong, the images undecorated. The occasional detail cut in by Thompson's son Matthew, also a sculptor, enhances the challenging resonance.

Thompson’s faith is tenacious, but his philosophy is generously and humorously flexible.

The stations for St Mel’s Cathedral have been an absorbing commitment for the past 12 months, but the completion of the Phillip memorial – his third piece of work for Westminster Abbey – commissioned by the Britain-Australia Society Education Trust, offered a useful diversion.

Arthur Phillip was in charge of the convoy carrying the first consignment of convicts from England to establish a penal colony in New South Wales. A humane captain and expert navigator, he brought all his ships safely through the 15,000-mile voyage to Botany Bay in 1788. There he established the colony, and what is regarded as the foundation of modern Australia, until ill-health forced his return to England five years later. He died in Bath in 1814, his importance and achievements by then largely unacknowledged, perhaps because of his anti-slavery opinions.

Thompson has selected a piece of Sydney sandstone for this work. "Because of where it will be placed, it was crucial to get it right. The flagstones in Westminster are all square, or diamond on the edge, and four of them have been taken up to slot this in between the tomb of the Unknown Soldier and close to the David Livingstone memorial."

Within the diamond frame, Thompson has circled the simple legend of name and dates, but its heraldic symbolism is carried in the narrow silhouette of a kangaroo at the bottom point.

“He’s down under. Literally,” says Thompson.