Prof. Paul Morris, in this lecture, comments on Louis Jacobs’s lifelong interest in heresy. He focuses particularly on Jacobs’s essay, published in a festschrift in honour of R. Seymour J. Cohen in 1991, on a series of responsa on the topic of heresy written by the late medieval Vilna rabbi Ephraim b. Jacob hakohen (see the essay here).
Prof. Morris reviews extensively the different approaches to heresy espoused by Jewish sages from the late antiquity to the modern period, which often react to contemporary heretics (such as Spinoza or, according to the mitnaggedim, R. Shlomo Zalman of Lyady) and heretical movements (most prominently in Jewish history karaism, sabbateanism, and frankism). He notes, however, that the threat of herem, or excommunication, which accompanied accusations of heresy, was rarely actualized. The speaker then reviews, using sources relating to the “Affair”, the allegations against Jacobs’s heresy and the calls for a formal excommunication issued by certain voices in Anglo-Jewry.
Finally, Prof. Morris examines a sermon entitled ‘Revelation’ delivered by Louis Jacobs at the New London Synagogue in 1964, with the view of considering its content and assessing whether it does constitute heresy or not.