By what basis do the Catholics change the original Jewish understandings of sexually acceptable acts within marriage? (Flawed question)

### The Catholic position. *There are many other sources, I just picked one at random* > "the unnatural vice." This may happen in several ways. First, by procuring pollution, **without any copulation, for the sake of venereal pleasure**: this pertains to the sin of "uncleanness" which some call "effeminacy." Secondly, by copulation with a thing of undue species, and this is called "bestiality." Thirdly, by copulation with an undue sex, male with male, or female with female, as the Apostle states (Rm. 1:27): and this is called the "vice of sodomy." **Fourthly, by not observing the natural manner of copulation, either as to undue means, or as to other monstrous and bestial manners of copulation.** > > Summa Theologica - Whether the unnatural vice is a species of lust? **Basically, if you are married the venereal act must always be unprotected and end inside.** They will often also point out this particular situation in Genesis 38, quoted from the NKJV to reflect the catholic preference for the MT Old Testament. > NKJV: 8 And Judah said to Onan, “Go in to your brother’s wife and marry her, and raise up an heir to your brother.” 9 But Onan knew that the heir would not be his; and it came to pass, when he went in to his brother’s wife, that he emitted on the ground, lest he should give an heir to his brother. 10 And the thing which he did displeased the Lord; therefore He killed him also. Right, so Onan pulled out and the average catholic person suggests that this was the problem. (I humbly disagree, but that's off-topic here) I think this side of the issue is well understood so let me show the Jewish side of it. ### The Jewish position (Talmud) The ancient Jewish views come from rabbinic interpretations like the Talmud and later writings. As Christians and Jews understand, sexual acts are supposed to be within marriage. And focus on procreation. A focus is not the same as the outright demand of the catholic position. Here are some quotes of the English from the Talmud in Nedarim 20b. > However, the Rabbis said: The halakha is not in accordance with the opinion of Yoḥanan ben Dehavai. Rather, **whatever a man wishes to do with his wife he may do. He may engage in sexual intercourse with her in any manner that he wishes**, and need not concern himself with these restrictions. As an allegory, it is like meat that comes from the butcher. If he wants to eat it with salt, he may eat it that way. If he wants to eat it roasted, he may eat it roasted. If he wants to eat it cooked, he may eat it cooked. If he wants to eat it boiled, he may eat it boiled. (Nedarim 20b:4 ) > The Gemara relates: A certain woman, who came before Rabbi Yehuda HaNasi to complain about her husband, said to him: My teacher, I set him a table, using a euphemism to say that she lay before him during intimacy, and he turned it over. **Rabbi Yehuda HaNasi said to her: My daughter, the Torah permitted him to engage in sexual intercourse with you even in an atypical manner, and what can I do for you if he does so?** (Nedarim 20b:6 ) I'm sure we are adult enough to understand the euphemism of a "turned-over table" here in the context of a woman who is upset about it. But I'm going to quote the Talmud again because I really don't want this euphemism to be misunderstood. > The Gemara wonders about the proof from Tamar itself: But weren’t there **Er and Onan**, her previous husbands, who presumably engaged in sexual intercourse with her? The Gemara responds: Er and Onan engaged in sexual intercourse in an atypical manner, i.e., anal intercourse, and therefore she was still a virgin. (Yevamot 34b:1 ) The verse about Onan has mixed opinions but from what I can tell primary objectionable act is that Onan was disobeying God by blatantly disregarding his levirate marriage obligation. Not even putting it in the wrong hole itself. Looking through other things on Sefaria I found all kinds of instructions like... > Approach her lovingly and passionately, so that she reaches her orgasm first. - Iggeret Hakodesh, 13th C. (found in this article ) Also, I looked in Mi Yodeya (J:SE) - What are reasons of מצוות עונה marital sex? 3. Wife is longing for Husband & 4. Husband simply does not want to be tempted to sexual sin. (Additionally the answer starts with wives have a right to sexual pleasure just as they do clothing and food... so yeah) ### Quick side by side | **Aspect** | **Catholic Position** | **Ancient Jewish Position** | |--------------------------|-----------------------------------------------------------|---------------------------------------------------------| | **Core Principle** | Sex must always unite procreation and unity; no exceptions. | Sex should prioritize procreation but allow marital freedom for pleasure or preventing sin. | | **Scriptural Basis** | Genesis 38 (Onan), natural law theology (Aquinas). | Genesis 38 (Onan), Leviticus 15, Talmudic interpretations. | | **Flexibility** | Rigid; universal rules apply to every act. | More flexible; depends on intent, context, and rabbinic opinion. | Ancient Jewish regulations are pragmatic and interpretive, shaped by rabbinic debate, and don’t enforce a universal procreative mandate for every act. Catholicism, with its rigid systematic theology (Augustine, Aquinas, etc), insists on procreation as mandatory in every instance. ### Things I've checked already... I've looked at these aspects so far... but I'm giving up and asking you guys now. - Jesus did not abolish the Law (Matthew 5:17-18) - Flee from sexual immorality (1 Corinthians 6:18-20) does not contradict the previous Jewish understanding in any way. - Galatians 3 // Acts 15 Both of these passages do not suggest that any previous sexual laws or understandings of immorality had changed. - The marriage as an icon of Jesus and the Church in Ephesians 5:25-33 doesn't retroactively change the previous understandings either, if anything it strengthens them. - And of course, we have the entire book of Song of Songs which urges us to Love God with the same passion as two people in passion. (This is mentioned here as well ) ### Question On what basis do the Catholics change the original ancient understandings on this subject? No traps here... honestly curious as, to why the Catholics made this rigid universal rule when none existed previously. Edit: Talmud is way too late to be valid in the format I presented. Making my question a frame issue. I'm not deleting this though as the answers are insightful.