Igros Moshe (Yoreh Deah 1:160): Concerning a conversion which was done by a Conservative rabbi which did not have the proper acceptance of mitzva and the immersion in the mikve was not in the presence of a beis din but rather was observed by two women. It is obvious that this conversion has no halachic significance because the acceptance of mitzvos is a necessary condition for conversion. Even if she accepted all the mitzvos of the Torah except for one it is invalid as is stated in Bechoros (30b). Furthermore the acceptance of the obligation to keep mitzvos has to be done before three judges and failure to do so invalidates the conversion even bedieved as is stated in Shach (Y.D. 268:9). Therefore there is a basis to question the validity of the conversion - even though there are Orthodox rabbis who also accept converts [who end up not observing mitzvos]. Despite the fact that “we are witnesses” (anan sahadi) that the majority of converts do not genuinely accept the mitzvos as is proved by the way they conduct themselves after conversion. In addition she is not going to be more observant then her Jewish husband for whom she converted. She sees that he violates Shabbos as well as many other Torah prohibitions. However there is a basis for saying that a convert who doesn’t observe mitzvos is nonetheless a valid convert bedieved since she said before the beis din that she accepted the obligation to observe the Torah mitzvos and it happens that sometimes such a convert truly accepts the mitzvos even though they don’t keep them afterwards. Therefore perhaps she should be considered as such a ger who does not observe the laws of the Torah after conversion. This despite the fact that it is clear to us because of her subsequent non‑observance that at the moment of conversion she did not accept the mitzvos in her heart but only said that she was accepting them. Even though I personally don’t find it reasonable for the sake of the rare individual to remove the “we are witnesses” (anan sahadi) of her subsequent behavior and to pay attention to the possibility that she was sincere in her thoughts at the time of conversion. However perhaps this is the reasoning of these Orthodox rabbis and there is some basis for their view. There is also a strong justification to assert that she is a valid ger from the fact that her husband – for whose sake she converted – does not observe Shabbos as well as many other prohibitions so that she assumed that there is not really such an obligation to observe mitzvos to be a Jew. Therefore she is like a non‑Jew who converted amongst non‑Jews which Shabbos (68a) states is a valid ger even though he still worships idols. The reason that he is a valid ger is because he has accepted upon himself to be like all the other Jews and this is considered a valid acceptance of mitzvos even though he knows nothing about the mitzvos. That is because knowledge of mitzvos is not critical to become a ger. It is only when he knows about the mitzvos and refuses to keep them that the conversion is not valid. We know this from the fact that he has no obligation to learn the entire Torah before he converts – he is only instructed in some of the mitzvos. Therefore even though the beis din told her that she must keep Shabbos, she thought that this was just merely desirable and that even if she didn’t keep Shabbos and other mitzvos she mistakenly thought that she was a good Jew. Therefore she mistakenly thought she had accepted all the mitzvos that a Jew is required in order to convert – even though this caused her not to fulfill the mitzvos. This is a possible justification to consider her to be a valid giryorus – even though she doesn’t keep all the mitzvos. It is a weak justification for those Orthodox rabbis who accept such converts so as not to view them inferior to laymen. [Despite this possible justification for a non‑observant ger to be a valid ger] nevertheless the mitzvos have to be accepted before a beis din. It is likely that the Conservative rabbis don’t do this because they don’t know the laws of conversion. In addition they are not careful to follow the law even when they know it. Consequently their conversions lack the proper acceptance of mitzvos - even of the most minimal type - which is critical for a valid conversion. In addition the Conservative beis din is invalid because they reject many fundamental principles of Judaism and transgress a number of prohibitions. Look at Choshen Mishpat (7:9) and Piskei Teshuva there in the name of R’ Akiva Eiger – that even transgressing a rabbinic law disqualifies a person from being a judge and this doesn’t require an announcement. In addition it is almost a certainty that they transgress many Torah prohibitions even though witnesses have not been accepted to testify to this but it is “like we are witnesses” (anan sahadi) that anyone who is called with the debased description of Conservative is presumed to violate many prohibitions and to deny many of the fundamentals of religion. I have already explained in one teshuva that someone who is presumed to be a heretic is invalid - even without formal testimony from witnesses. This is true even for leniences. I don’t have the time to go into greater detail concerning this matter. Therefore it is quite obvious that a conversion done by a Conservative rabbi has no significance.
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