Despite its atmosphere of perceived religious tolerance, Amsterdam, or “The New Jerusalem,” had its limits. It made room for heretics, but managed to excommunicate them too

Much is made of a small number of New Jews, contemporaries of Menasseh, who were drawn Amsterdam by the same perceived atmosphere of tolerance which had attracted the families of conversos from Spain and Portugal. Their refusal to accept Judaism as understood by the community authorities there and the subsequent uproar they caused have received extraordinary attention often to the exclusion of the majority community and its accepted leaders. This group has at times been wrongly portrayed as quite representative of local Jewry at the time and as suffering unreasonably without any mention of the distinguished community leaders involved, including Menasseh, nor any explanation of the reasons for their treatment. He was certainly involved with two of these dissenters – Uriel Acosta and Baruch Spinoza – apparently as their teacher as well as being a member of the local Beth Din concerned with their cases.

Uriel Acosta (sometimes called Uriel da Costa) was born in Portugal about the year 1585 and was descended from conversos. Both he and his father were Church officials. Gradually he came to reject Christian teachings and, following the death of his father, fled with his remaining family to the Amsterdam community in 1617.

However he was not able to accept the tenets of the Jewish religion as practiced there. In his first work in Portuguese (Propositions against Tradition) he questioned traditional beliefs generally and then in 1624 inveighed specifically against belief in the immortality of the soul (An Examination of the Traditions of the Pharisees).

The religious leadership was outraged. He was accused of blasphemy against religion – his book was burned and da Costa was fined and excommunicated. He went to Hamburg but he was ostracized and in 1633 returned reluctantly to Amsterdam saying he would be an ape amongst apes!