St. Thomas was born a Jew and was called to be one of the twelve Apostles. His birth and death dates are unknown. He lived before the formal establishment of the Catholic Church but is recognized as the patron saint of architects.

St. Thomas is best known for his role in verifying the Resurrection of his Master. Thomas' unwillingness to believe that the other Apostles had seen their risen Lord on the first Easter Sunday earned him the title of "doubting Thomas."