The gift of human sexuality allows us to choose, or not to choose, to participate in one form of God's creation. This book presents the understanding of human sexuality that divine revelation offers us. It is intended primarily for Christian adults who wish to know not only what kinds of sexual behavior are right or wrong but also why such behavior is right or wrong for those who seek to follow Christ.   This expanded version of The Christian Meaning of Human Sexuality includes a work on the theology of natural family planning that was unfinished at the time of the author's death. Father Paul Quay considered the matter in the light of faith and not simply on the natural level, which was his approach to the study of human sexuality in general.   Understanding sexuality as part of the Christian mystery is offered us through the Scriptures and the living Tradition of the Church. Father Quay uses both to show what sexuality means in Christian terms. His insightful descriptions of the complementarity of male and female, a complementarity that is psychological, spiritual, and physical, are exceptionally illuminating. He explains the Bible's frequent use of the symbolism of marriage and sexuality to reveal the relationship between God and his people and the relationship of spouses to one another. He also reflects on the natural symbolism of the human body and of spousal communion.