In 1959, upon being ordained a priest of the Prelature of Opus Dei, the Author, Fr. John Portavella, was asked by Founder, St. Josemaria Escriva, to exercise his ministry and help in the apostolic work in the United States. Fr. John remained in the USA until 1967, when St. Josemaria asked him to serve in the Philippines.

Fr. John exercised his ministry in Cebu City from 1981 to 1991. There, he imparted courses on Theology for Lay People and taught Medical Ethics at the Cebu Doctors College of Medicine. From 1991 to 2011, he served in Iloilo City, guiding souls of men and women from different walks of life, and of secular priests and seminarians. For many years, he was the Assistant Chaplain at Westbridge School for Boys. He also spent five years teaching Metaphysics and Philosophy of Nature at the St. Vincent Ferrer College Seminary in Jaro, Iloilo.