In my previous post I discussed the basic problems with effective interfaith dialog.
All of which may be unimportant if Judaism is a prosletizing religion. Not in the sense that anyone would suggest that Jews are obligated to convert all people to Judaism. But if there is an obligation to bring all humans to conform to the 7 mitzvos benei Noach then perhaps we must overcome the problem rather than simply acknowledge it.
First, it looks to my eye that in practice most of the Jews who sell pendants and rings in the diamond exchange on 47th Street (in New York City) hold like Tosafos that trinitarianism conforms to the 7 mitzvos. Because otherwise selling crosses would be prohibited even in a market dominated by non-Jews. I don’t know which idea is dominant in the texts of halakhah. And yet, it seems to be common enough practice.
Second, those trinitarians who place the three-ness in the realm of their god-as-perceived would be observant Noachides according to all opinions. And a Moslem (assuming they are part of the non-murderous majority) also complies to the 7 mitzvos. Today’s more educated Hindus also teach that their 3.1 million gods are human perceptions of One Incomprehensible Divinity.
My point being, Noachidism is a meta-religion, a criterion a specific religion may or may not conform to. It might (see next issue) mean proselytizing to true polytheists, but it doesn’t mean “believe this specific religion”.
Third, are we obligated to teach Non-Jews? Or are we obligated to set an example for them to teach themselves? If we are supposed to passively lead them by example to Noachidism, not actively teach it, then it’s hard to call that missionizing.
The Sifri in Va’Eschanan can be read either way. The Rambam takes it to mean there is a mitzvah, either chiyuvis or qiyumis (either an obligation or a good thing to do if you happen to do it). I can’t tell. The Lubavitcher Rebbe clearly stated the Rambam obligated (Hil’ Malekhim 9 onward), but I think that is his novellum. The naive reading (pashut peshat) of the Rambam would be not to convert them to a religion of Noachidism, and only that he permits teaching them the parts of the 7 mitzvos they come to you to learn. Tosafos (Chagiga 13a “ein”) clearly says it’s a non-obligatory mitzvah to teach them the laws they are trying to observe. In contrast to the prohibition against teaching them the rest of Oral Torah. Unclear about the mitzvos they aren’t yet drawn to. If it weren’t for the LR, I would assume there is only one opinion shared by both rishonim.
Related: There is a Torahitic prohibition of lifnei iver (“[placing a stumbling block] before the blind”, enabling another to sin) with respect to leading a non-Jew to violate one of the 7 that they couldn’t otherwise do. But the rabbis saw no need to enact mesayeia lidevar aveirah (handing someone over to sin) when the issue is helping them do a sin that could have done (with more difficulty, and perhaps motivation-killing difficulty) without you, as they have with aiding a Jew to violate one of the 613. What are we suupposed to conclude from that?