Elizabeth was reasonably sure she was too old to have children. Sarai was reasonably sure she was barren. Why not use the withdrawal method just for grins? (Not an anachronism now, is it?)
Elizium I agree this is a very perceptive and interesting borderline scenario in this discussion.
Here we can see most clearly the relationship between one’s “intention” (ie purpose) and the objective “object” of action immediately intended, and the circumstances attending that intended purpose. And depending on how one philosophically understands the relationship between these three fonts that determine the goodness of a “human act.”
First up we must define what the **object **is here. And here we run straight into an issue. Catholic Teaching normally says that the external action we call “coitus interruptus” is an object whose intrinsic nature is contraceptive.
But, as Aquinas makes clear, we must not fall into the temptation of thinking that exactly similar scenarios (eg “coitus interruptus”, or “killing someone”) seen with the eye must always specify the same
object. For example, two men are fighting and one dies. Was the “object” of the surving man’s intention murder or self defence? Aquinas says that usually we can tell from visible details of the scenario which it was…
But sometimes we cannot. Sometimes lethal self-defence and murder can be exactly the same in every discovered detail. What then defines the difference? … it is the (unknown)
intention of the survivor at the moment he struck the fatal blow.
At this point many people say…but circumstances cannot justify the intrinsic evil of an act. And this is true. But they have misunderstood “circumstances.” And we are not yet looking at the “human act” as a whole, we are just looking at the
object of the “human act” (which is only part of the “human act” as a whole).
In any “human act” there are at least two sets of “circumstances”. First we look at the details of the scenario at hand (in English we could call these “circumstances” I suppose) so we may correctly define/identify the sort of
object that was immediately intended/purposed (eg was it murder because the other person was innocent, was it self defence because the other person had a gun and our man was unarmed). This discovery is usually trivial.
If at this stage we are happy that the
object intended has been well defined/discovered we will then know from Church teaching whether this object is intrinsically evil. If it is, end of story, the act as a whole was evil. No intention (the 1st font of a human act) is good that purposes an intrinsically evil
object. Then we look at the 2nd set of circumstances/consequences (the 3rd font of a human act) that surround the person’s intention/purpose (the 2nd font of a human act). Were they coerced? Were the actual bad results small or big. These circumstances may mitigate the imputed guilt of the wrong done (it cannot be denied though).
The point is this: the details of the scenario at hand are NOT the same thing as the circumstances/consequences surriounding the intention/purpose. The details of the scenario at hand are NOT the circumstances of the “2nd font.”
Therefore, in some cases, the intention of the person (if not denied by the details of the scenario at hand) can make all the difference in deciding what sort of moral
object is actually under discussion.
So lets apply all this to “coitus interruptus.”
Usually the Church defines such a scenario (seen with the eye) to be an act of contraception because it is understood that 99% of the time it is done (and seen to be done) as birth control. This was exactly the case with Onan.
However, why would a sterile couple (or a husband with a well pregnant wife) choose to do such a thing? it doesn’t make sense. Hence the visible details of the scenario at hand tell us that the husband must have a non-contraceptive motive/intention for doing this.
Elizium you raised the example of Elizabeth and Zechariah. Why would Zechariah do such a thing? What is his immediate intention? A contraceptive intent/purpose cannot be present because you acknowledge they both considered having a child impossible. Yet, it couldn’t even be because he had leprosy (lets pretend its communicated through exchange of bodily fluids like AIDs) because withdrawal hardly gives any surity in that regard.
But lets assume our OT husband thought this was a good way of not passing on leprosy.
Then the object of his intention is would appear to be masturbation, deriving pleasure from the procreative organs. It would be hard to argue that withdrawal sex is good because of the unitive purpose. Most theologians would not regard such sex as meeting the definition of “unitive sex”. (Which incidentally is why IVF is also wrong even though procreative - because the “sex” involved is not unitive).
So in short, this looks to be a sin whose object is masturbation.
Iam sure Zechariah and Elizabeth would never do that, it is intrinsically evil

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