Over at Canon Law Blog, Dr. Ed Peters states that the teaching of the Magisterium condemning contraception as intrinsically evil is infallible under the ordinary and universal Magisterium (About That Humanae Vitae Rumor). Then he badly misstates the infallible teaching, by claiming that all sexual acts outside of a valid marriage are excluded from the very definition of an intrinsically evil act of contraception.
So a question arises as to whether a Catholic who claims to believe an infallible teaching of the Magisterium (specifically a divinely revealed truth that must be believed with divine and catholic faith), but who adheres to a distorted version of that teaching, is guilty of heresy.
Some heresies are a simple denial of a truth, e.g. God does not exist. Other heresies are a distortion of truth, e.g. the Lutheran doctrine of the Eucharist, where the bread and Christ are both present. But what if the distortion is merely a limitation, e.g. that divorce and remarriage is not within the definition of adultery?
When a teaching must be believed with divine and catholic faith, can the individual substantially change the teaching, and only then believe? No, of course not. Any substantial distortion of a Catholic dogma is a type of failure to believe, because the truth itself is not accepted, but only a similar falsehood. Altering truth, whether by addition, subtraction, or distortion, is a type of rejection of that truth.
Therefore, the claim that contraception is only intrinsically evil within marriage is material heresy. For the claim excludes from
moral condemnation a vast number of uses of contraception, and substantially changes the meaning of what must be believed. Many Catholic authors are promoting a distorted version of Church teaching on contraception, which is material heresy.
When is that same claim formal heresy? Only if the person realizes that this definition of contraception is contrary to magisterial teaching. If the error is made by a sincere but mistaken conscience, then the heresy is material, but not also formal.
It is quite a serious problem, though, that several prominent Catholic authors are mistakenly teaching an heretical version of the magisterial condemnation of contraception. For the difference between the correct teaching and the error is not merely academic. The restricted definition of contraception implies that very many uses of contraception, perhaps most uses, are not intrinsically evil, or at least not condemned by the Church. And such a claim about a serious moral subject can harm souls.
Another problem is that the methodology used to redefine contraception is being applied to other intrinsically evil acts. And the result is always the same: a restricted redefinition of the sinful act justifies that sin in many cases.
The recent dust up about the bombings of Hiroshima and Nagasaki is a case in point. Deacon Toner begins by justifying some lies, and then uses the same disordered principle to justify the atomic bombs, which are a type of mass murder. So this justification of many uses of contraception, by redefining what is and is not contraception (as if contraception only exists in a valid marriage) is part of a larger moral problem in the Church, whereby ethicists change the very definition of an intrinsically evil act in order to justify that act in some cases.
Heresy is a grave sin, which does much harm to souls, to minds and hearts, in some cases to bodies as well.
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