BACKSTORY: Uriel Da Costa’s path off the derech

Artist's rendering of Uriel Da Costa
Artist's rendering of Uriel Da Costa

At the recent Agudath Israel convention in Stamford, Conn., the closing keynote speeches addressed the phenomenon of Jews going “off the derech” – that is, Jews who decide to become unaffiliated with Judaism. The tendency now among community leaders and outreach professionals appears to be to concentrate on preventative measures, putting an emphasis on the care that must be shown towards those at risk.

At the same time, there is less of an emphasis placed on addressing the philosophical and theological questions of those who break with the community on the basis of those concerns. Historically, however, those who went off the derech sometimes did so because of theological or philosophical reasons. Baruch Spinoza, who I would call the godfather (or natural father) of all who leave the Jewish faith, serves as an obvious example.

Regardless of the political situation in Amsterdam, where Spinoza lived, or the position that his views regarding the providence of God and the authorship of the Bible put the community in – and some argue that both of those factors may have forced the community’s hand in the decision to excommunicate him – the systematic and comprehensive views Spinoza lays out in his Theological Political Treatise are not the thoughts of someone who would be able to live within the community.


Spinoza’s predecessor (and possible influence), Uriel Da Costa, belonged to a Marrano family, and first converted to Judaism because he found theological difficulties in Christian doctrine. In somewhat similar fashion to Spinoza, Da Costa’s first break with Judaism was also a matter of principle.

In fact, as Miriam Bodian, a professor of Jewish history,  explains, it was based on his rejection of the oral law, which he believed stood in contradiction to the old law. Da Costa’s claims, which he expressed in his Examination of Pharisaic Traditions (1623), were taken quite seriously by the Jewish community of Portugal, where he lived. Indeed, the community directed those concerns to the colourful sage Leon de Modena. Modena’s response is recorded in his book, Magen Ve-zina.

Even so, Da Costa’s first break with the Jewish community was only a partial one. He reconciled with the community in 1628, but not fully, since he still did not keep the dietary laws, and he was excommunicated again four years later. This time, the process of reconciliation was a long and humiliating one, and it took seven years until he was admitted again.

Nevertheless, in perhaps the clearest expression of how deeply he clung to his heterodox views, Da Costa took his own life not long afterwards. This interpretation is supported by the autobiography, entitled Explanation of a Life, found near his bed, in which he expresses faith in a God that cares only that humans ought to live moral lives.

As Tamar Rudavsky notes, in Explanation of a Life, one of Da Costa’s main arguments is that rabbinic Judaism has no notion of natural law, the term for a universally valid, moral framework. Given that he originally studied canon law at the University of Coimbra, it not surprising that he thought in those terms. In fact, it is possible that Da Costa reflected on that issue for some time. In an earlier work, Examination of Pharisaic Traditions, he already mentions natural law, namely, in the way that the moral framework seems to be incompatible with a particular rabbinic ruling.


Rudavsky convincingly argues that Da Costa was wrong about natural law being incommensurable with rabbinic thought. Although the term natural law does not appear to be in use until it is found in the work of Joseph Albo in the 15th century, a similar idea was found in rabbinic, Gaonic, and medieval thought.

But whether Da Costa was right or wrong on that particular issue is beside the point. Despite our most serious efforts, those who go off the derech  and leave the faith sometimes do so for theological and philosophical grounds. And in those cases, even our deepest expression of care may not be enough. 

Jonathan Milevsky is a PhD candidate in religious studies at McMaster University in Hamilton, Ont.