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Adventures in Jewish Studies

The Association for Jewish Studies Podcast

Episode 10: The Conversion Episode



Jeremy Shere: Hello there. For returning listeners, welcome back to the podcast. And for first- time listeners, it's good to have you. So, as you know from the introduction, I'm Jeremy Shere. And I'm here with my co-host and fellow producer, Jen Richler. Jen, how are you? 

Jen Richler: I am fine. I guess I'm not actually here with you, but I am virtually here with you. So, hello. It's nice to virtually be with you.

Jeremy Shere: Yeah, right. We are still social distancing. We're doing this remotely, if anyone's wondering. But anyways, Jen, we recently celebrated the holiday of Shavuot. And, you know, Shavuot isn't as well-known as some of the other holidays, like Rosh Hashana the Jewish new year like Passover. So Jen is going to give us a little primer on Shavuot. Go for it, Jen.

Jen Richler: I'm going to give a primer? Okay, well, I'm not exactly an expert. You're kind of …

Jeremy Shere: I’m putting you on the spot. 

Jennifer Richler: You are. Okay. Let's see…What do I know? Well, for starters, I do know that Shavuot takes place exactly fifty days after the end of Passover. And originally, back in ancient times, it was one of shalosh regalim — that’s the three pilgrimage festivals when Israelites brought agricultural offerings to the Temple in Jerusalem. 

Jeremy Shere: Right. And then at some point, after the Second Temple was destroyed by the Romans in 70 CE, the rabbis of the Talmud reconfigure the holiday to be about the biblical story of the Israelites receiving the Torah from God on Mount Sinai, after the Exodus from Egypt, because there was no longer a temple to bring the offerings to. 

So part of the way that we celebrate Shavuot today is by going to the synagogue and reading from the Book of Ruth, which is about a Moabite woman named Ruth, who marries an Israelite man from Judea. And then when he dies, Ruth returns to Judea with her mother-in-law and remarries another Israelite man. And at the very end, the book reveals that Ruth is the progenitor of a family line that several generations later results in none other than King David himself. 

Jen Richler: Wow. That's quite a story. But Jeremy, why do we read it on Shavuot? What does it have to do with the people of Israel receiving the Torah? 

Jeremy Shere: Good question, Jen. Why don't you tell them? 

Jen Richler: Oh, not again.

Jeremy Shere: I'm just kidding. Well, actually it's a good question. And that gets a little complicated. Because, honestly, it's not really clear why we read the Book of Ruth on Shavuot. There are many expert opinions on this, and in fact, that's what we're going to explore in this episode — in particular, the common idea that Ruth is the first convert to Judaism, and what that may have to do with receiving the Torah at Sinai. And we're going to do this in two parts. In part one, we'll look at the idea of conversion in the book of Ruth in the Torah and in rabbinic writings.

And in the second part, we're going to tell the stories of a Muslim and a Christian who converted to Judaism during the medieval and pre-modern eras, when becoming a Jew was dangerous. And we'll explore what their stories have to tell us about conversion and about Jewish identity then and today. Let’s get started.


During the time when the judges ruled ancient Israel, a famine struck the land. And so a Judean family — Elimelech, and his wife, Naomi, and their two sons — left the Promised Land for the neighboring kingdom of Moab. 

Jen Richler: And there, the sons married Moabite women. One is named Orpah; the other, Ruth. But then, tragically, Elimelech and his sons die, leaving behind Naomi and her Moabite daughters-in-law.

Jeremy Shere: The story is according to the Book of Ruth, which scholars believe was most likely written during the late fifth or fourth century BCE. In the most dramatic and moving part of the story, Ruth pledges to stay with Naomi and go with her to Judea. Here's the scene as depicted in the 1960 movie The Story of Ruth.

[clip from film]

Jen Richler: So, there it is. Ruth pledges to go with Naomi back to the land of Judah and to adopt her culture and her God. In other words, for the first time in Jewish history and literature, we see a non-Jew converting to Judaism. 

Jeremy Shere: There's just one problem. 

Christine Hayes: So Ruth is held up as being the first convert, which is rather ironic when you consider the fact that she's referred to as Ruth the Moabite.

Jeremy Shere: This is Christine Hayes, a professor of Religious Studies at Yale. As she points out, at the end of the story, when Ruth is remarried to an Israelite named Boaz, even he refers to her as Ruth the Moabite. 

Christine Hayes: Now, this doesn't mean that Ruth doesn't really join the Israelite community — she does, but there's no formal process of conversion.

Jen Richler: Instead, according to Hayes, she joins the community first through marriage, and then, even more significantly, through her devotion to her Israelite mother-in-law. 

Christine Hayes: Her motivation for joining the community was her deep existential love for Naomi, her fidelity to her mother-in-law and her desire to be with her. She does say, after all, “Your people will be my people, and your God, my God,” but the people come first. 

Jeremy Shere: In other words, Ruth is drawn to the people of Israel by her love for an individual Jew, not because she's made an independent choice to adopt the laws and customs of Judaism. And as Ruth the Moabite, she apparently hasn't given up or renounced her ties to her ancestral homeland and culture.

Jen Richler: So why, then, is Ruth widely seen as the first convert? A main reason is because of a passage in the rabbinic commentary on the Book of Ruth. 

Christine Hayes: The rabbis take the speech of Ruth when she declares, “Your people will be my people, your God, my God” — and they parse it to indicate that she is accepting the Torah, she’s accepting the commandments, she’s accepting God. She even says, “and Naomi, if you won't convert me, get out of my way, because I'm going to convert, I have such a zeal for the Lord.”

Jeremy Shere: The problem, Hayes says, is that this reading of the Book of Ruth is an anomaly. The majority rabbinic opinion takes a different approach.

Christine Hayes: The rabbis even say in Ruth Rabbah, the Book of Ruth, or Megillat Ruth, the scroll of Ruth, doesn't come to teach us about the laws of purity or impurity or about prohibitions and commandments and so on. It teaches us simply chesed and the pathway under the wings of the Shechinah, which is a pathway of chesed. And they then reached for other biblical figures who exemplify other pathways into the community of Israel, which are not in this mode of a confessional, religious transformation. 

Jen Richler: In fact, it's not very difficult to find biblical examples of non-Israelites who joined the people, or at least lived among them. The Bible refers several times to the necessity of dealing fairly with the ger… 

Christine Hayes: …which is simply a resident alien, a person who's a non-native who lives with, resides with, the community to some degree or level of incorporation and absorption. Now to the extent that there might actually be intermarriage and a child produced, that child would be fully Israelite.

Jeremy Shere: Right from the beginning, Abraham, the first Jew, is said to acquire followers during his journey throughout the land of Canaan, and the Bible describes many intermarriages. 

Christine Hayes: So Moses, of course, has two foreign wives: Tzipporah is a Midianite, and he also has a Cushite wife. They produce fully Israelite children — no language or terminology to describe these processes of absorption.

Jen Richler: When Moses leads the people out of Egypt, they're joined by a mixed multitude of non-Israelites who stand with them at Sinai when they receive the Torah. And later, during the time of the Israelite monarchy, many kings married foreign women and had sons who became future kings. 

Christine Hayes: So we know that this was always going on and there were always non- Israelites and later non-Jews joining the community in some way — some having a kind of a hybrid status, even in the sense that they were members of the community, but might still have been identified as “so-and-so the ger” or “so-and-so the Moabite.” So it’s a hybrid community. There wasn't a sense that they were mutually exclusive identities, that you had to turn away from one thing in order to adopt the other. So there was no formal ritual or process of conversion as we know it today.

Jeremy Shere: But it wasn't the case that anyone or any group could simply join the Israelite nation. For example, intermarriage with Ammonites and Moabites was generally prohibited, because those groups attacked the Israelites during their journey toward the Promised Land. And the Canaanites were seen as morally corrupt, so they were off-limits too.

Christine Hayes: But there was no universal ban on intermarriage. And that's because in the Bible, the people of Israel clearly don't consist only of people born into the tribe. At the time that God calls Abraham to form a people, a goy, he says ve’esecha l'goy gadol, “I will make of you a great nation.” He doesn't define what that nation will consist of. He certainly promises many offspring, but he also says that Abraham will be the father of many nations, in the plural. 

Jeremy Shere: So while lineage is important, it's not definitive. After all, Abraham had two sons, Isaac and Ishmael, but Ishmael becomes the founder of his own people, the Ishmaelites. Same goes for Isaac’s son, Esau, who marries two Canaanite women and gives rise to the nation of Edom. 

So biological descent doesn't really determine who's in and who's out. And as Hayes notes, neither does religion. 

Christine Hayes: We certainly know of the patriarchs that they worshipped household gods, and the prophets continue to upbraid the Israelites throughout their history for their worship of the Ba’al or other gods.

They didn’t therefore declare that they weren't Israelites because they engage in these practices. They were bad Israelites, perhaps, but they didn't lose their Israelite identity because they worshipped other gods. So it wasn't even necessarily a religious definition. 

Jen Richler: The point is that biblical sources draw a picture of Israelite identity as fairly open and multi-dimensional. There are elements of ethnicity, biology, and religion, but no one factor dominates.

Jeremy Shere: Until, that is, the fourth century BCE, when a cohort of Jews returned to Judea from Babylonia, where they'd been living in exile since the destruction of the First Temple in 586 BCE. They were led by Ezra, a scribe, or possibly a priest, who was instrumental in reforming the Jewish community in Judea on the basis of the Torah, or law as presented in the five books of Moses. And a central tenet of that law, according to Ezra, was what Hayes calls the “holy seed ideology.”

Christine Hayes: He sees the intermarriage that's happening in the period of the restoration, probably the fourth century BCE, and he is disturbed, because, as he says, “the holy seed of Israel has mixed with the seed of non-Israelites.” He gives a long list of all of the non- Israelites, including some groups that were permitted in marriage by Deuteronomy. But he now lumps them all together, because holy seed is holy seed. In his view, the seed, the DNA, the biological seed of Israel has been separated from other seed and can't be mixed with it.

Jen Richler: Holy seed ideology was a stark departure from the more open nature of Israelite society and culture before the Babylonian exile, at least as depicted in the Bible. But Ezra had his reasons for taking this extreme position. According to the book of Ezra, it was a time of crisis, when many Jews had forgotten their language and culture and were in danger of disappearing for good.

Christine Hayes: They laid that all on the door of intermarriage and they wanted, therefore, to throw out all of these foreign — they're described as foreign wives at this point, not husbands. And they wanted to throw out all of these foreign wives because they saw a real threat to Judean identity. 

Jeremy Shere: Ezra’s non-mixing policy was unpopular, to say the least.

Christine Hayes: It was a radical innovation and it caused an uproar. If you read the books of Ezra and Nehemiah, people are weeping in the streets. He's telling everyone to throw out their non-Jewish wives and their non-Jewish children. 

Jen Richler: Ezra's strict intermarriage reforms didn't last. During the Second Temple period, from 516 BCE to 70 CE, dozens of Jewish sects proliferated. And they had differing views on intermarriage and Judean identity. Some, like the community whose writings were found in the caves of Qumran near the Dead Sea, adopted Ezra's holy seed philosophy and rejected conversion and intermarriage. 

Jeremy Shere: Most others rejected Ezra’s reforms as too stark a departure from the traditionally more open, covenant-based attitude toward Judaism. In fact, some scholars claim that the Book of Ruth, with its proto-convert heroine, was written during this period as a counterpoint to the holy seed view. 

Jen Richler: The more open approach was favored by the Jewish philosopher Philo and the Jewish historian Josephus, who lived toward the end of the Second Temple period.

Christine Hayes: They certainly understand the role that lineage has played, but they also do have a covenantal notion of Israelite identity, which allows for conversion. And in fact, this is one of the traits of the Judean tradition that they see as being admirable. And they hold this up in the eyes of their Gentile readers as a remarkable trait, that Moses has created a system whose laws are open to those who wish to embrace them. So this is something they see as a virtue. 

Jeremy Shere: This notion became codified during the rabbinic period, from roughly the first century CE to the close of the Babylonian Talmud, around 600 CE. For the Talmudic sages, Jewish lineage was sufficient for claiming Jewish identity, but it wasn't a necessary condition. 

There was a variety of opinions. For example, some rabbis held that certain rituals were not accessible to converts because those rituals entailed the declaration of a formula that alluded to actions or activities that had happened to the fathers. And these people can not literally claim to be fathers.

Jen Richler: But other rabbis found creative ways around this line of reasoning, for example, by pointing to Abraham, who God promised would become the father of many nations. 

Christine Hayes: And therefore that means that Abraham really is the father of all of these different groups and the land was also promised to him. So it is all right for a ger to say, “You have given the land, the land that you promised to our fathers.”

Jeremy Shere: From the second through the fifth centuries of the Common Era, something like a formalized process of conversion began to take shape. Circumcision was required for male converts, and the Talmud records a debate about whether female converts were required to be immersed in the purifying waters of a mikvah. Generally, becoming a Jew was increasingly seen as the process of a person exchanging their former religious and cultural identity with their new Jewish one.

Jen Richler: As Hayes points out, it’s important to recognize that rabbinic debates about the nature of conversion were happening during the rise of Christianity and the extension of Roman citizenship to all people living in the Roman empire, which changed how people thought about group identity and belonging. 

Christine Hayes: And I think the rabbis work out their notion of conversion in conversation with those, not wholly adopting one model or the other, but negotiating these different ideas and carving out something that's really sui generis. It's really saying someone who is not of the lineage, if you will, that you're now of the lineage. You’re family, but not entirely. There are still certain ways in which Jewish law takes notice of the different lineage and origin of this person. So it's not a hundred percent.

Jeremy Shere: At this point, you may be wondering, beyond the biblical period, how many non-Jews were actually trying to convert to Judaism? And the answer is — not very many. After the destruction of the Second Temple in 70 CE, when Jews were exiled from Judea and spread throughout the Roman empire and Arab lands, they were at best tolerated, to differing degrees. 

Jen Richler: By the medieval era, conversion to Judaism was deemed illegal in Christian and Islamic lands.

Ronnie Perelis: It was a capital punishment. 

Jeremy Shere: This is Ronnie Perelis, Associate Professor of Sephardic Studies at Yeshiva University. 

Ronnie Perelis: If a Christian converted to Judaism, the Christian who converted, and everyone who helped him convert, would be put to death.

Jen Richler: Converting to Judaism meant not only risking death, but also being exiled from your community, at a time when social and economic life were deeply entwined with family life.

Jeremy Shere: And yet, some non-Jews did convert to Judaism, despite the hardship and significant risk. For example, sometime during the twelfth century, a Muslim man in Cairo, who became known as Ovadia the Convert, converted to Judaism. And we know about him because of a letter he wrote to Rabbi Moses ben Maimon, the famous philosopher and Torah scholar known as Maimonides. Ovadia’s letter posed a question:

Ronnie Perelis: The question was basically, “A lot of the prayers start with ‘The God of Abraham, God of Isaac, God of Jacob,’ or ‘God of my fathers,’” all those phrases of paternity. And he was saying, “Well, I know who my fathers are. I know how far my Gentile roots go. I shouldn't lie. I can't say ‘God of my fathers,’ I can't say ‘God of Abraham, my father,’ because it's not true. And that's an important principle in prayer. You should say things which are truthful. You're speaking before God, right?”

Jeremy Shere: Perhaps to Ovadia’s surprise, Maimonides’ answer to the question of whether a convert should invoke the forefathers in prayer was an emphatic yes. 

Ronnie Perelis: You should invoke those fathers, because they are your fathers. Because you are like a child of Abraham, you are like that person who gave up everything that was familiar, followed God into a strange land, and serves him wholeheartedly. 

Jen Richler: Maimonides’ view was not the only one. Another philosopher and Torah scholar, Yehuda Halevi, took a different approach. 

Ronnie Perelis: They won’t ever really attain the same thing that a Jew can. We’ll accept them. You have to love them. And there's all sorts of laws about protecting them. But they can't have the same level of spiritual and intellectual attainment that a Jew can.

Jeremy Shere: But this was a minority opinion. Maimonides’ take was more widely accepted and set the tone for converts to Judaism going forward into the early modern era, which is when we encounter a fascinating convert named Manuel Cardoso. Cardoso was born into an old Catholic family in 1585 in Portugal. 

Ronnie Perelis: His father was a merchant in the dye and wool business and did a lot of business with England. And when Manuel was about 14, his dad sends him to England to study, to learn the language, and to apprentice with one of his business partners in England. 

Jen Richler: Cardoso was in England during the height of the Protestant reformation, when papal authority was being challenged. Caught up in the ferment, Cardoso began to question Catholic doctrine and read the Bible on his own, without the mediation of a priest or bishop. 

Ronnie Perelis: And he says that one day, he went to London and he bought seven books on the seven different sects. And he lists them, “…and Baptist and Calvin…,” and this and that. And he goes through them and he says, at the end, I found the most reasonable to be Calvinism. 

Jeremy Shere: Word of Cardozo's apostasy reached Portugal. During a visit home, he was arrested and ended up in a cell with a converso, a Jew whose ancestors had converted to Catholicism during the Spanish Inquisition, but was accused of secretly practicing Judaism. 

Ronnie Perelis: And the young Manuel is shocked. He just…”What, there are people who live the Bible, people who keep the Sabbath on Saturday?” and all these things. And he says, this threw him into a shock, because he thought Calvinism was true, he’s rejected Catholicism… now what does he have? Is he going to be a Jew? 

Jeremy Shere: Actually, yes…but not quite yet. 

Jen Richler: First, he’s sent to a reform school for wayward Catholics, where he encounters more conversos. He connects with them and then eventually lives with them.

Ronnie Perelis: And eventually, after one failed escape, he escapes from Lisbon and hooks up with the family of Dias Milão, who was this accused Judaizer that he used to know from the prison, in Hamburg. And there he describes being embraced, converting, including a circumcision ceremony and taking the name of Abraham Pelegrino Guer.

“Pelengrino” in Portuguese means “wanderer” or “pilgrim,” and guer, obviously, in Hebrew, “convert” — that was the name he chose.

Jeremy Shere: Cardoso, now, Pelengrino Guer, ended up working for a Jewish family in the port of Danzig, in Germany. And when the family was accused of ritually murdering one of their Christian servants, Cardoso told them to flee while he stayed behind to protect their property. He was beaten by a blood-thirsty mob and imprisoned. 

Ronnie Perelis: He eventually makes it to Amsterdam where he is, again, part of the Portuguese community, works as a shamash, as a beadle, in the synagogue and lives out his life in Amsterdam and writes down this story.

Jen Richler: Fast forward several centuries to today, when ideas about conversion have changed significantly. Converting to Judaism is no longer illegal in the Western world, of course. As of 2019, according to the Pew Research Center, roughly 17% of American Jews are converts. And the process of conversion now depends on which denomination of Judaism you’re converting to: Orthodox, Conservative, Reform, and other denominations each have their own rules and customs. 

Jeremy Shere: But in some very basic sense, the feelings and ideas that drove Ruth the Moabite, Ovadia the Convert, and Cardoso to become Jews are still at the heart of what attracts some non-Jews to Judaism today. And although the process of converting is less fraught than it was centuries ago, it can still pose significant challenges.

Jen Richler: As Hayes notes, we often favor those who become Jews for religious reasons over those who convert for marriage. The story of Ruth, she says, pushes back against this way of thinking.

Christine Hayes: It's not clear to me how and why it would be convenient for Ruth to do what she did. And these kinds of differentiations really devalue those who are drawn to the community because of their closer intimate ties with a Jewish human being. Ruth's life- altering choice wasn't convenient, and it was no less noble or courageous or existentially transformative, just because it was taken out of a deep and selfless attitude of chesed, or lovingkindness, and fidelity to an individual Jewish person.

Jeremy Shere: For Perelis, the story of Manuel Cardoso can be an inspiration for people today, who feel compelled by religious conviction to become a Jew. But while modern-day converts, thankfully, no longer have to face the trials that Cardoso endured, for some, especially for people of color who don't look like white Jews of Ashkenazi background, being accepted by the majority Jewish community is not always easy.

Ronnie Perelis: Do they stand out? What is it like? Are they accepted? You know, people complaining, “How many times do people have to ask me how I'm Jewish? I was born this way. Or I chose this, but why does that matter?” And that really comes out again with skin color as a marker, as a differentiator.

Jeremy Shere: So returning to the question that we began this episode with, why do we read the Book of Ruth on Shavuot, well, maybe it's to remind us that receiving the Torah at Sinai was a transformative event for all Jews. At that moment, like Ruth, the entire Jewish nation, native-born and strangers alike, chose to become converts and to be re-fashioned as God's chosen people.

Ronnie Perelis: That's very powerful. It's saying you became a new person at this moment, and the charge of Sinai, the ethical, religious charge of the commandments made you a different being, a different group. And so every year when we celebrate the giving of the Torah, what people who are practicing that are saying is, “We need to be renewed,” or “The Torah has to renew us.”


Episode Guests


Christine Hayes

Christine Hayes, PhD, is the Robert F. and Patricia R. Weis Professor of Religious Studies in Classical Judaica at Yale University, and the immediate past president of the AJS. Her published works include several books and many articles in Vetus Testamentum, The Journal for the Study of Judaism, The Harvard Theological Review, and various scholarly anthologies. Her most recent book, What’s Divine about Divine Law? Early Perspectives, received the 2015 National Jewish Book Award in Scholarship, a 2016 PROSE award for best book in Theology and Religious Studies from the American Publishers Association, and the 2016 Jordan Schnitzer Award.


Ronnie Perelis

Ronnie Perelis, PhD, is the Chief Rabbi Dr. Isaac Abraham and Jelena (Rachel) Alcalay Associate Professor of Sephardic Studies at the Bernard Revel Graduate School of Jewish Studies of Yeshiva University. His research explores connections between Iberian and Jewish culture during the medieval and early modern periods. His essays on Sephardic history investigate the dynamics of religious transformation within the context of the crypto-Jewish experience. His most recent book, Blood and Faith, explores family and identity in the Sephardic Atlantic world.

Episode Host


Jeremy Shere, PhD

Jeremy Shere, PhD, is a podcast producer based in Bloomington, Indiana. Jeremy earned his doctorate in English Literature and Jewish Studies from Indiana University. He is currently the producer of the Frankely Judaic podcast for the Jewish Studies program at the University of Michigan.

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