The Old Operating Theatre Museum and Herb Garret is situated in the roof space of St Thomas’ Church. The Church was dedicated to St Thomas Beckett and it probably originated as a chapel of the medieval hospital, but it is not known when it was first built on the present site. There was certainly a medieval church and it is known that one Richard Chaucer was buried there. Additions were made to the church in the early 17th-century, including the bell tower. By 1697, however, the Governors of the Hospital reported the church was so decayed that people were afraid to go inside.
The church was not the only building in need of repair, and a fundraising campaign, led by the President of the hospital, Sir Robert Clayton, was already underway with the aim of completely rebuilding the hospital. By the early 18th-century, the hospital was transformed into an elegant Neo-Classical edifice.
St Thomas’ Church was rebuilt between 1698 and 1702 in a more Neo-Classical style, with the first sermon recorded in July 1703. The new church was a small structure built of red brick and white stone dressings with a single nave and a flat roof. It was fitted out with a large garret constructed in the ‘aisled-barn’ tradition. The church shows many similarities to two other London churches: St James’ Piccadilly (1684) and Saint Benet Paul’s Wharf (1685). Both of these churches were designed by the brilliant architect of St Paul’s Cathedral, Sir Christopher Wren. Wren was Governor of St Thomas’ at the time the Church was built, and had given £500 to the Hospital rebuilding fund. It seems highly probable his team was involved in its design, in any event, it was to be built by his master mason Thomas Cartwright, who had worked with him at the Church of St Mary-Le-Bow.
The rebuilding cost £3,718, which included compensation to the owners of two small houses to the east of the old church which were pulled down. This suggests that the previous church had occupied the west end of the present building. It was also built on a slightly different alignment. In addition, fifteen shillings (75p) were paid “for taking up and burying the several corpses in the old church in order to lay a foundation.”
The church is the oldest surviving part of St Thomas’ Hospital’s Southwark site. The adjoining buildings on St Thomas’ Street, houses for the Hospital Treasurer; the Receiver of the Rents; the Apothecary and the Minister of the Church, were begun in 1704.
The Church was renamed in the Reformation and lost its designation to Thomas Beckett in exchange for St Thomas the Apostle. Clearly the authorities were keen to end any association with a pro-Catholic Martyr but were unsure that the local population would take to a radical renaming. The change to St Thomas the Apostle was therefore convenient.
In the 19th-century the church was made redundant and became the Chapter House of Southwark Cathedral. In the 1980s the church was taken over by the Chapter Group who are Lloyd’s insurance brokers. The Old Operating Theatre Museum remains in the roof space of the church.