Said to have been founded at the gates of Peterborough monastery, the Hospital of St Thomas the Martyr was originally named St Thomas of Canterbury. It was founded by Abbot William of Waterville (1155-75) and provided a hospital for the poor. Abbot Benedict completed the building between 1177 and 1194 and Abbot Acharius granted money from the chapel of St Thomas the Martyr (a huge draw to pilgrims and therefore a good source of income) to pay for the nuns who cared for the patients and to provide provisions for the sick. Many of the pilgrims visiting the abbey at this time would have been unwell, so this was a rather clever plan to use pilgrims' money to pay for the sick.
References:
'Hospitals: St Leonard & St Thomas Martyr, Peterborough', in A History of the County of Northampton: Volume 2, ed. R M Serjeantson and W R D Adkins (London, 1906), p. 162. British History Online http://www.british-history.ac.... [accessed 12 July 2019].
A Peterborough Cathedral Timeline https://www.peterborough-cathedral.org.uk/history.aspx [accessed 12 July 2019]
A List of the Abbots of Peterborough https://en.wikipedia.org/wiki/Abbot_of_Peterborough [accessed 12 July 2019]