The historic belief of Roman Catholicism is young-earth creationism. But today, the predominant belief among Roman Catholics is theistic evolution. That is, all life evolved from a common ancestor which means Adam and Eve were not the first human beings and they had human parents. This viewpoint must allegorize Genesis 1-3 instead of treating it as literal history. Theistic evolution fits in well with the allegorizing tendency Rome has toward the Bible.
Pope John Paul II embraced theistic evolution as true in his address to the Pontifical Academy of Sciences:
“Today, nearly half a century after the publication of the encyclical, new knowledge leads to the recognition of the theory of evolution as more than a hypothesis. It is indeed remarkable that this theory has been progressively accepted by researchers following a series of discoveries in various fields of knowledge. The convergence, neither sought nor provoked, of the results of work that was conducted independently is in itself a significant argument in favor of this theory.”
This belief is shared by Pope Francis and Vatican astronomers who argue that young-earth creationism is “almost blasphemous” and that the Bible should not be used as a science textbook. Things have certainly changed from the time Galileo was condemned by the Catholic Church for teaching that the earth revolves around the sun. Now contrast what Pope John Paul II said with the Pontifical Biblical Commission of 1909:
“Genesis 1-3 is historical, not a fictional or mythological narrative, nor derived from pagan mythologies nor are they allegories, nor partly historical and partly fictional.”
It affirmed as true the creation of all things by God at the beginning, the special creation of man, and the formation of the first woman from the first man. The statements of this commission were given approval by Pope Pius X. Because this commission and Pius X believed that all of Genesis 1-3 is historical and not allegorical or fictional, they believed that Adam was literally created out of the dust of the ground by an act of special creation. But in theistic evolution, Adam had a mother and a father and was not literally created out of the ground. This means that John Paul II and Pius X had two different interpretations of Genesis and approaches to the question of evolution. So, which one are we supposed to believe? How does papal infallibility help us out when it comes to the question of evolution?