Thomas Tien Ken-sin was born in Chantsui, Yanggu, (Shantung province) to Kilian Tien Ken-sin and his wife Maria Yang. Baptized in 1901, he studied at the seminary in Yenchowfu before being ordained to the priesthood by Bishop Augustin Henninghaus on June 9, 1918. Tien then did pastoral work in the Yangku Mission until 1939. He entered the Society of the Divine Word on March 8, 1929, in the Netherlands, taking his first vows on February 2, 1931, and his final ones on March 7, 1935. He was raised to Apostolic Prefect of Yangku on February 2, 1934.