Bishop Sebastian Vadakel was born on 7 October 1952 at Vilakumadam in the eparchy of Palai as the second of the six children of Mr. Devasia and Mrs. Mary Devasia. After completing the school education from St. Joseph's High School, Vilakumadam, he joined Deepti College, the minor seminary of the Missionary Society of St. Thomas the Apostle. He had his major seminary formation at St. Joseph's Seminary, Mangalore. He was ordained priest on 19 April 1979. His first appointment was as professor at Deepti College, Melampara and late as its Rector. In 1982 he was sent to Rome for higher studies where he took his doctorate in canon law. On his return he was sent to the Ujjain Mission where he served as assistant parish priest in Khadi and Shajapur and parish priest at the Cathedral, Ujjain. During this time he took B.A. and M.A. in Hindi Literature. He also served as visiting professor of a number of Major Seminaries and formation centers. On 18 May 1993, he was elected the Director General of MST which office he held until 18 May 1998. He was nominated bishop of Ujjain n 5 June 1998 to succeed Mar John Perumattam and was ordained bishop on 8 September 1998 at St. Mary's Cathedral, Ujjain.