history - Precedent for Forbidding Conversion

The Syrian community has a Takkanah in place which bars conversion. In addition to forbidding conversion under their own auspices, they also "Never accept a convert or a child born of a convert", as well as bar the children of intermarried couples from entering or marrying with the community.

This incredibly strong "Edict" has no parallel among current Jewish communities that I know of. Is there any historical precedent for such an exclusionary doctrine? Have any other communities in the past adopted a similar decree?

Answer

I am not Syrian, nor do I claim to know about why the Syrians do what they do, but this seems to be similar to what was done in the days of Kings David and Solomon.

Yevamos 24a:

ת''ר אין מקבלין גרים לימות המשיח כיוצא בו לא קבלו גרים לא בימי דוד ולא בימי שלמה א''ר אליעזר מאי קרא {ישעיה נד-טו} הן גור יגור אפס מאותי מי גר אתך עליך יפול אבל אידך לא

It was taught in a braysa: we do not accept converts in the times of the Messiah. Similarly, they did not accepte converts, not in the days of (King) David, nor in the days of (King) Solomon. Rabbi Eliezer says, what verse teaches us this? (Yeshayahu 54:15) "הֵן גּוֹר יָגוּר אֶפֶס מֵאוֹתִי מִי גָר אִתָּךְ עָלַיִךְ יִפּוֹל," "Behold, the one with whom I am not, shall fear, whoever mobilizes against you shall defect to you;" but no one else.

(translation of gemara is mine; the translation of the verse in Yeshayahu is Judaica Press, copied from Chabad.org)

Similarly, on Yevamos 76a:

ויתחתן שלמה את בת פרעה מלך מצרים גייורי גיירה {מלכים א ג-א} והא לא קבלו גרים לא בימי דוד ולא בימי שלמה מידי הוא טעמא אלא לשולחן מלכים

"And (King) Solomon married the daughter of Pharaoh, king of Egypt" (Melachim I 3:1). She must have converted. But how could that be? Isn't it true that they didn't accept converts, not in the days of (King) David, nor in the days of (King) Solomon? The answer is that they didn't accept converts in those times because of "the table of kings."

Rashi, there (sv מידי):

האי דלא קבלו גרים אלא משום דלא הוו מגיירי אלא לשולחן מלכים הא בת פרעה לאו צריכא להכי שהרי בת מלך היתה

That that they didn't accept converts was only because those that came to convert came for the "kings' table" (i.e., to partake of the wealth of the Jewish people). Pharaoh's daughter clearly didn't convert for this reason, because she was the daughter of a king.

(above translations mine)

We see from this that we should only take converts at a time when things aren't going so great for the Jews, because then we know that the conversion was for good reason. However, when things are going really well (as in the times of King Solomon, and the Messiah), then converts should not be accepted, because at those times they're probably trying to convert due to "שלחן מלכים," and just trying to take advantage of the Jews' good position in society.

Again, I don't know if this is why the Syrian community has taken up this practice; it's just that the circumstances seem similar to me.