In June 1715 Thornhill was officially awarded the much-coveted commission to decorate the dome of St Paul's Cathedral in London, for which he had been competing since 1709 (see Tate L01481). This small oil is one of a set of eight (see Tate L01482-3 and L01485-9) which probably forms a presentation set painted after the eight scenes from the life of St Paul as finally finished in the cupola. Thornhill strictly adhered to the 1709 and 1715 rulings that the dome be painted with figurative histories taken from the Acts of the Apostles, and that they be executed in monochrome, simulating sculptural relief. Thornhill worked on the cupola until 1717, for which he was paid £4,000, and on other areas of the dome until 1721 (see Tate L01482).
The Sacrifice at Lystra is the third episode in the cycle, which moves anti-clockwise round the dome, starting with Paul's conversion positioned directly to the east. It is taken from Acts 14: 8-18 which tells of Paul and Barnabas's miraculous cure of a cripple, whereupon the pagan inhabitants of the city mistook them for Mercury and Jupiter and made moves to sacrifice an ox: 'the priest of Jupiter that was before their city, brought oxen and garlands unto the gates, and would have done sacrifice with the people. Which when the apostles, Barnabas and Paul, heard of, they rent their clothes …'.
Thornhill's treatment of the subject owes a great debt to Raphael's (1483-1520) tapestry cartoon (circa 1514-16), then hanging at Hampton Court (now Victoria and Albert Museum, London). The series was regarded as the greatest example of painting in England. As in the Raphael, Thornhill places Paul to the left, standing on steps before the people of Lystra, tearing at his cloak, with Barnabas immediately behind him. The sacrificial altar appears in the foreground, and the ox to the right. While Raphael's composition is dominated by a central figure raising his axe, about to slaughter the animal, Thornhill has the crowd listening intently to Paul's words, their eyes fixed on his actions. In fact, the many preparatory designs that exist for this and the other St Paul episodes, at the British Museum, Courtauld Galleries and Victoria and Albert Museum, make it clear that Thornhill went through several changes of mind before finalising the most visually effective composition, incorporating and rejecting elements, including those taken from Raphael, as he went.
Arline Meyer, Sir James Thornhill and the Legacy of Raphael's Tapestry Cartoons, exhibition catalogue, Miriam and Ira D. Wallach Art Gallery, Columbia University in the City of New York, 1996
Carol Gibson-Wood, 'The Political Background to Thornhill's Paintings in St Paul's Cathedral', Journal of the Warburg and Courtauld Institutes, vol. 56, 1993, pp.229-37
Edward Croft-Murray, Decorative Painting in England 1537-1837, I, London 1962, pp.73-4 and 271b