The Church teaches infallibly in any of three ways: (1) Papal Infallibility, (2) Conciliar Infallibility, (3) ordinary and universal Magisterium. Infallible teachings are required to be believed by every Catholic with divine and catholic faith, that is, with the full assent of faith (theological assent). Any Catholic who rejects an infallible teaching of the Magisterium is guilty of at least material heresy. Whoever knowingly obstinately rejects or knowingly obstinately doubts such a teaching is guilty of formal heresy. Formal heresy carries the penalty of automatic excommunication.
The Roman Catholic Church has taught infallibly on the subject of Adam and Eve at the Council of Trent.
Now it is true that the Council only mentioned Adam, and not Eve. But the Council teaches that all men are “born propagated of the seed of Adam,” [Decree On Justification, Chapter III.] and they cannot have been so propagated without Eve. And Sacred Scripture teaches us about both Adam and Eve, in both Testaments. So no one could possibly believe that Adam existed, as an individual historical person, and not also Eve.
“1. If anyone does not confess that the first man, Adam, when he had transgressed the commandment of God in Paradise, immediately lost the sanctity and justice in which he had been constituted, and incurred, through the offense of that type of prevarication, the wrath and indignation of God, and therefore also the death with which God had threatened him beforehand, and with death, captivity under the power of him who thereafter held the empire of death, that is, the Devil; and the whole Adam, through that offense of prevarication, was changed for the worse in body and soul: let him be anathema.” [Decree on Original Sin]
It is not possible to hold two contradictory ideas at the same time: the above dogma and the claim that Adam never existed as an individual historical person. The idea that Adam and Eve represent a number of progenitors of the human race, such that they never existed as two individual persons, is entirely incompatible with the required belief that “the first man, Adam…transgressed the commandment of God….”
Any Catholic who claims that Adam and Eve did not exist as two real historical persons is guilty of heresy.
“2. If anyone asserts that the prevarication of Adam harmed himself alone, and not his posterity; and that the sanctification and justice, received from God, which he lost, he lost for himself alone, and not also for us; or that his defilement, through the sin of disobedience, has transfused only death and the punishment of the body into the whole human race, but not also sin, which is the death of the soul: let him be anathema. For he contradicts the Apostle, who says: “through one man, sin entered into the world, and through sin, death; so also, death was transferred into all men, into all who have sinned.” [Romans 5:12].” [Decree on Original Sin]
The Council of Trent also infallibly taught that the sin of Adam adversely affected the whole human race, in body and soul. So the idea is heretical that some human persons were not descended from Adam and Eve. The dogma is that the whole human race is descended from Adam and Eve, without exception. So the human race consists of Adam, Eve, and their descendants only. Even Jesus, in His human nature, and the sinless Virgin Mary are descendants of Adam and Eve.
Any Catholic who claims that some human persons are not descendants of Adam and Eve is guilty of heresy.
Notice also, in the quotes above, that Catholics must believe that all human persons (other than Jesus and Mary) have inherited original sin from Adam, because Adam sinned, because we are all descendants of Adam. Original sin affects us adversely in body and soul. We are conceived without sanctifying grace. We are conceived and born with fallen bodies, subject to concupiscence, disease, injury, and death.
There are several different modern theories on original sin, which contradict the above infallible teachings. The claim is heretical that human persons (other than Jesus and Mary) are conceived with sanctifying grace, or that original sin is not inherited, or that original sin is obtained by imitation or in some way other than inheritance.
Obstinate doubt about any formal dogma is also heresy. If a person says, “I don’t believe Adam and Eve ever existed,” that is heresy by obstinate refusal to believe. But if a person says, “Maybe Adam and Eve existed, or maybe not,” that is heresy by obstinate doubt. The Magisterium requires the full assent of faith, regardless of what your own reasoning says, for every infallible teaching. Saying, “maybe it’s true, or maybe not” to a dogma is heresy. Heresy is a rejection of the requirement to believe with a divine and catholic faith.
As I explain in my book, Adam and Eve versus Evolution, Catholics cannot believe that Adam and Eve were produced solely by evolution. For this would not permit the dogmas of Trent on original innocence, original sin, and Adam and Eve as our first parents, to be also held as true. God must have intervened to create Adam and Eve, and placed them in Paradise, where they fell from grace by deliberate grave sin.
The idea that evolution produced mankind, and then, subsequently, God infused an intellective immortal soul into two individuals (or more) is contrary to dogma. For then Adam and Eve would not be created in original innocence, but would have been created by evolution in a fallen state.
On the subject of evolution, the most that we can possibly hold, as an opinion that is not contrary to any Catholic teaching, is that evolution produced beings without an intellective immortal soul, mere animals, without the ability to reason abstractly and without free will, whose bodies were anatomically modern, but who were not true human persons.
Although the following idea is not explicitly stated as an infallible teaching, I see no possibility compatible with Conciliar dogma other than that God created Adam and Eve miraculously, as adults. They were not conceived or born of any parents, and they were never children. They began as sinless adults, and then they fell from grace.
I do not think that Catholics must reject all or most of evolutionary theory. However, any claims in the modern theory of evolution contrary to Catholic teaching must be rejected. We can hold that evolution occurred, and that in this way various forms of life developed on earth. We can hold that the form of the human body developed by evolution. But then we must also propose that God intervened to create the first two individual historical human persons, Adam and Eve. Otherwise, our position would be contrary to dogma and therefore heretical.
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