Abrantovich was born in Navahradak. He first studied there and then in Saint-Petersburg at the Roman Catholic seminary and the Theological academy. He graduated with the degree of Master of Theology and was ordained to the priesthood on November 9, 1908. As one of the best students at the academy, Abrantovich received scholarship for study at the Catholic University of Leuven, Belgium, where he received Ph.D. in 1912.