Because Ong had entered the Jesuit order in 1935, he devoted the subsequent years of his young life to his lengthy Jesuit formation - finally being ordained a Jesuit priest in 1946 - the year in which Ong turn thirty-four.

Source: https://www.opednews.com/articles/Walter-J-Ong-on-Historica-American-History_American-Republic_Cultural-Cognition_Cultural-Evolution-230910-771.html

These practices, called the Spiritual Exercises, were set out in the early 16th century by Saint Ignatius of Loyola, the founder of the Jesuit order, and intended as a meditative tool in the form of a monthly program.

Source: https://worldcrunch.com/culture-society/mama-antula-saint