Catholicos Baselios Thomas I was born in the Cheruvillil family of Vadayambadi in Puthencruz to Mathai and Kunjamma on July 22, 1929. Early part of the life of Mor Baselios Thomas I was full of sufferings. Though he belonged to an aristocratic family, by the time he was born the family had seen bad days. As a child he had frequent bouts of illness which affected his education. His mother used to take the young boy frequently to the nearby Malekurishu Dayro where the relics of late Patriarch St. Elias III had been interred. One night, as his mother prayed with the young boy on her lap, she had a vision which prompted her to dedicate the boy to the service of the church. Within days, the boy's illness was entirely cured.