It is possible that Thomas belonged to the gens (clan) Záh, which acquired large-scale domains in Transdanubia.
[5] A royal charter of Béla IV of Hungary, issued on 3 October 1269, narrates that Thomas had founded a monastery in a once existing river island near Ercsi on the left bank of Danube (present-day administratively belongs to Szigetújfalu).
[2] According to the aforementioned document, Thomas unlawfully donated the tithes of Vál and Dörgicse to the newly established monastery during the foundation to financially support the monks.
[6] Art historian Géza Entz placed the palmette carvings in parallel in the 12th-century stonemasonry workshops in Székesfehérvár, Somogyvár and Pécs.
[2] The building blocks of the abandoned monastery were used in the reconstruction of the Saint Leonard church in Szigetújfalu in the 18th century.