[Claud]

the moral difference between onan says he will knowingly have sex intending to cheat the reproduction commandment to be fruitful and multiply by wearing a condom and onan says he will knowingly have sex intending cheat the reproductive commandment to be fruitful and multiply, by artificially controlling his times of sleeping with his wife, to artificially avoid her fertile eggs is a purely theological distinction without a moral difference

No, it isn't. As I said before, NFP differs from artificial contraception the way dieting differs from bulimia. In the former, you are simply restraining yourself. In the latter, you are not restraining yourself at all--you are committing the act and then deliberately frustrating its natural purpose. We call dieting a good thing, and an example of self-restraint. No one ever says that about bulimia--it's a psychological illness, a misuse of food.

Let's think this through here. If deliberately engaging in sex at naturally infertile times was just as immoral as contraception, it would be immoral to have sex after menopause. It would be immoral to have sex during pregnancy. Clearly, neither of those is the case, right? There is no immorality in having relations even when we know the act will most likely be infertile.

As long as, of course, we *do* nothing to the act itself to deliberately make it infertile. That is what Onan did. And that is why he was struck down.

But note that under the Law, Jewish women were not niddah (ritually unclean) during pregnancy--they could have relations even though they were infertile during those times. So obviously God saw a distinction between natural infertility and artificial infertilility.

[timm22]

There is no immorality in having relations even when we know the act will most likely be infertile. As long as, of course, we *do* nothing to the act itself to deliberately make it infertile.

So the distinction boils down to acts *causing* infertility vs. acts *taking advantage* of naturally-occurring infertility?

So presumably, a couple that has sex after menopause (or maybe a medically-necessary ovariectomy) is not doing anything wrong. Even though they are enjoying the pleasure of sex, without the possibility of procreation, they are morally blameless since they did not cause the underlying infertility.

Am I right so far?

[Wuli]

“In the former, you are simply restraining yourself.”

as i said - you’re artificially affecting results - either way

with contraception, in accord with reason, with NFP, to conform to not getting chastised by the priest at next ‘confession’

“As long as, of course, we *do* nothing to the act itself to deliberately make it infertile.”

this is not morality, it is simply priestly theology