The National Gallery’s show-stopping Christmas offering invites us to step into the picture – and Laura Gascoigne is captivated

Visiting the Benedictine abbey of St Adrian near Brussels in 1600, Albert and Isabella, rulers of the Spanish Netherlands, saw an altarpiece in the Lady Chapel they simply had to have. A richly detailed Adoration of the Kings, it had been commissioned nearly a century earlier by local nobleman Daniel van Boechout from an up-and-coming young Flemish painter called Jan Gossaert. It was the largest picture the artist would ever paint, and the most alluring. The couple made the abbey an offer they couldn’t refuse and took the painting home to hang over the high altar in their palace chapel in Brussels.

Like its ravishing colours, the allure of this picture never faded. When it appeared on the London market nearly three centuries later, the auctioneer sold tickets to view it at a shilling a pop. In 1911 it entered the collection of the National Gallery, where it has attracted the admiration of generations of visitors astonished at its brilliance. Now, with the aid of digital technology, a new generation is being given the chance to examine it in previously undreamt-of detail.