**Abstract**

For nearly a century Catholic Church teaching on Sexuality evolved greatly. Changes in science and the teaching of other Christian churches begged for a fresh start. John Paul II, elected pope in 1978, attempted to update that teaching by providing new background arguments, without changing any of the strictures in the foreground. John Paul II insisted on necessity of total love, allowing for no exceptions. He claimed that divorce was impossible because the spouses retained no control over their marriage promises. Homosexual activity was judged to be morally deficient. Likewise the recent arrival of reproductive technology was largely condemned for breaking the sexual unity of the spouses. But fertile sexual activity was newly appreciated as the important activity of spouses cooperating with the creative activity of God. In the twenty-first century the Church's official teachings continues to be reformed, but their relevance is widely questioned as social norms continue to drastically change.

**Keywords:** John Paul II, total love, contraception, natural family planning, divorce, homosexuality, reproductive technology, canon law
