He was ordained into priesthood in 1998 with the Dominican order. He was a full-time professor and was promoted to become Dean of one of the university's oldest schools - the Faculty of Philosophy.
In July 2024, Ang was reappointed by Fr. Gerard Timoner III to a second four-year term. Archbishop José Tolentino de Mendonça, the prefect of the Dicastery for Culture and Education issued the “nihil obstat” declaration, in line with University of Santo Tomas' statutes (art. X), with the Holy See's approval. He was installed on September 9, 2024 at the Santísimo Rosario Parish by Rev. Fr. Filemon I. Dela Cruz Jr. OP, Prior Provincial of the Dominican Province of the Philippines and University Vice-Chancellor. During the appointment process, Fr. Isaias Tiongco, O.P. served as acting rector from May to July 2024.[6]