Matulaitis was orphaned at an early age, with his father dying in 1874 and his mother in 1881. In his pre-teens, Matulaitis developed tuberculosis of the bone in his leg, from which he suffered the rest of his life. Matulaitis was ordained to the priesthood on 20 November 1898, then professed as a religious in the Marian Congregation in 1909; on 14 July 1911, he was elected superior general of the Congregation of Marian Fathers. He reformed the Marians of the Immaculate Conception, changing their constitution, habit and way of life.