The quote given in this passage explains how Young thought about the idea of religion. He states that religion is human transformation as a response to our perceived ultimacy. Our perceived ultimacy refers to our awareness of the fact that we are mortal, and that our lives are finite. Because of our own mortality, humans seek certain values in their lives, and one among these is that of transformation.
This idea applies to scientology. Scientology promotes a set of beliefs that are meant to encourage deep understanding of humanity, as well as a deep connection with past lives. A scientologist attempts to transform himself by learning about his past and gaining awareness that allows him to connect with extraterrestrial beings. The acknowledgement of past lives addresses the subject of ultimacy.
This idea is also present in Medieval Christianity. Medieval Christians believed that all men carry the original sin, and that, as sinful beings, we are all tempted by evil. In order to reconcile our ultimacy with the will of the Lord, it is necessary to improve ourselves and live in purity. Some of the habits that ensure this are prayer, blind faith, celibacy and charity.