
The Old Sacristy, also known as Cappella del Sacro Chiodo, was built around 1444 on the right flank of the church of Santissima Annunziata to house the precious relics bought by the Hospital approximately one century earlier, until then kept in the Chapel of the Mantle.
The arrangement and decoration of the Sacristy reflect, in accordance with the Renaissance rules, the advanced culture of its client (former promoter of the famous fresco cycle of the Pilgrims’ Hall), Rector Giovanni Buzzichelli, whose coat of arms decorates the corbels and the recent Florentine and Lombard experience of the pittor dello Spedale Lorenzo Vecchietta, the painter of the important fresco cycle.
The Arliquiera, a wardrobe for the relics also painted by Vecchietta, was put in the Sacristy in 1445. It is currently entrusted to the National Picture Gallery of Siena.
An iconographic programme of great complexity and suggestion was worked out around the relic of the Sacred Nail, the most venerated piece among those purchased by the Hospital. It includes the mural paintings depicting the Christological cycle with the Articles of the Creed with reference to the New and Old Testament, painted between December 1446 and September 1449.