Transformation: A Man and His Works

Tuesday, January 19, 2021
Isaac Orobio de Castro was born in Portugal in the year 1620, to a family of Marrano Jews, forced to keep their religious practice and heritage a secret. He studied philosophy and medicine and went on to practice as a physician and teach in Seville and later Salamanca. When living in Spain, he was denounced by a thieving servant and subsequently held and tortured by the Inquisition until he finally confessed his Jewish affiliation. His family then moved around until finally settling in Amsterdam, a country with a thriving Jewish population. There, Isaac changed his name from Balthazar and openly began practicing and studying Judaism.

He went on to write a number of philosophical and apologist works defending rabbinic Judaism, a number of which could not be published due to their ‘sensitive’ nature, quite critical of Christianity. Writings such as “Prevenciones divinas contra la vana idolatria de las Gentes” (Divine Forewarnings against the Vain Idolatry of Gentiles) circulated in manuscript form instead, and it is said that portions of that work were then translated into French in 1770, when the treatise grew in popularity.

MS 759

This manuscript, from 1812, is a translation from the French into Hebrew. It begins with an overview of Isaac Orobio’s life, and then goes into the body of his work. The manuscript’s first half reveals that God warned the Jews against Christian beliefs through specific passages in the Torah. The second half refutes various Christian interpretations of biblical (Old Testament) passages.

The translator appended to the work a brief history of the life of Jesus, to provide further demonstration that he was simply a man, and not a divine being. The book’s title in Hebrew is Sefer Nekamat Yisrael – “Book of Israel’s Retaliation.”


In 1838, the first English translation of Orobio’s work was printed, this time called “Israel Defended.” The translator was a young woman named Grace Aguilar, born in London to a family descended from Spanish-Portuguese exiles. This was her first translated work, and she went on to write a number of books of her own. In her preface and through the mode of her translation, Aguilar toned down the hostility of Orobio’s original work as she felt a greater deal of respect and admiration for the Christians of her provenance in Protestant England. In her preface, she explains at some length the difference in position for the Jews of an enlightened liberal England, and how much improved their lot is when compared to the tortures endured by the original author under the “bigoted cruelty of Catholicism.”

The title page in fact lists the work as “Not Published,” and historian Yosef Kaplan suggests that this was a careful decision made to allay any potential concerns of proselytization. Marking the work this way would suggest that it was being used within a select group of Jews and not intended for Christian readers – Aguilar’s caveats in her introduction while likely intended for her Jewish audience, may also have served to mitigate any alarm of a Christian reader, should the book happen to fall into his or her hands.

GX O O74I2

This first printing of the French translation of Orobio’s “Prevenciones Divinas” was retitled “Israel Vengé.” The translation work was done by one named only as “Henriquez” when the book was published by Baron Holbach in 1770.

As mentioned in our previous posts on Orobio, his works were quite critical of Christian belief and therefore went unpublished for many years, though there are numerous surviving Spanish and French manuscripts of Orobio’s writings from the late 1600s and onward. A number of these manuscripts, including “Prevenciones Divinas,” serve as the basis for the compilation published by Holbach.

Holbach, one of France’s prominent free-thinkers, used the writings of Orobio to express his criticism of the Catholic Church in an indirect way. Though he thought the Mosaic Law was equally unenlightened, he still used Orobio’s arguments to condemn Catholic belief. He also strategically printed this item in London and not his native France, to avoid complications of French censorship.

The owner of this first edition, Eliphas Levi, included a biography or Orobio at the beginning of this book, signed 1861.

MS Acc 722

“Ve-Da Ma Shetashiv Le-Apekoros” (Know How to Respond to a Heretic) or in Spanish, “Sabe lo Que Responderas a los Hereges.”

Beginning in the mid 17th century, the Jews of Amsterdam, with their population swollen by the Spanish and Portuguese exiles, came to the newly conquered Dutch colony of Curacao in droves. Those of you have been following along in the Orobio series may have realized that this means that at the time Isaac Orobio and his family was arriving to the safe haven of Amsterdam, many Jews were leaving it to seek opportunities elsewhere. The congregation “Mikve Israel” that was established in Curacao in 1654 is the oldest Jewish congregation in the Americas. As an aside, in 1964 Mikve Israel joined together with Temple Emanuel, a Reform congregation, and their building that was built in 1732 is the oldest synagogue in the Americas where services have been held continuously.

This work of Orobio’s, copied in 1789 about a hundred years after his death, would likely have been passed down by someone in Amsterdam familiar with Orobio or his work and brought over to the emerging Dutch colony. We hope to learn more about this manuscript and its relation to Orobio’s other works.

Did you enjoy this series on Isaac Orobio, a truly fascinating character in Jewish history? To learn more, check out the authoritative books about Orobio’s life authored by Professor Yosef Kaplan, held in the Klau Library.

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