Sad experience or personal fanaticism underlies the oft-cited statement—in reality a play upon Isa. xiv. 1—that proselytes are as burdensome to Israel as leprosy<ref>Yeb. 47b, 109b; Ḳid. 70b; 'Ab. Zarah 3b; Ket. 11a; Niddah 13b</ref>; or the dictum that proselytes will not be received during the days of the Messiah.<ref>"Yad," Issure Biah, xiii.-xiv.; ib. 'Abadim, ix.; Yoreh De'ah, 268</ref> While evil upon evil is predicted for the "meḳabbele gerim"<ref>propagandists; Yeb. 109b</ref>, the proselytes themselves, notwithstanding their new birth, are said to be exposed to intense suffering, which is variously explained as due to their ignorance of the Law<ref>Yeb. 48b</ref>, or to the presence of an impure motive in their conversion (e.g., fear instead of love), or to previous misconduct<ref>Yeb. 68b</ref>. Nevertheless, once received, theywere to be treated as the peers of the Jew by birth.
According to R. Simeon b. Laḳish, proselytes are more precious at Sinai than Israel was, for the latter would not have taken the "kingdom" upon himself had not miracles accompanied revelation, while the former assume the "kingdom" without having seen even one miracle. Hence an injury to a proselyte is tantamount to an injury to G-d.<ref>Tan., Lek Leka, beginning; Ḥag. 5a</ref> The proselyte might marry without restriction.<ref>"Yad," Issure Biah, xii. 17</ref> The descendants of Ammon, Moab, Egypt, and [[Edom ]] formed an exception: the males of Ammon and Moab were excluded forever, though no restriction existed against marriage with their women. Descendants of Egyptians and [[Edomites ]] of either sex were proscribed in the first and second generations; the third enjoyed full connubial rights. But these restrictions were assumed to have been rendered inoperative by Sennacherib's conquest, and therefore as having no authority in later times.<ref>"Yad," l.c. xii. 17-24</ref>
Besides the proselytes already mentioned, all belonging to the Roman period, there are records of others later. Among these were the kings of the Jewish Himyarite empire; Arab tribes (before the 6th cent.); Dhu Nuwas; Ḥarith ibn 'Amr; the Kenites; Waraḳah ibn-Naufal; the Chazars. Many also must have come from the ranks of the Christians; this would be the natural inference from the prohibition of conversion to Judaism issued by the Councils of Orleans, repeating previous prohibitions by Emperor Constantine. The code of Alfonso X. made conversion to Judaism a capital crime.<ref>Graetz, "Hist." ii. 562; iii. 37, 595</ref>
