Moixè ben Nahman, Bonastruc de Porta

This article formulates and provides arguments to support the thesis
that Moses ben Nahman, the famous 13th-century Jewish writer, and Bonastruc de
Porta, to whom Latin documents of the time refer, were one and the same person.
After explaining the origin of the doubts some authors have voiced in that respect,
the article discusses the practice of using two names, one liturgical and one
for everyday life, which was widespread among Jewish males in Catalonia. The
main body of the article comments, one by one, on the seven Latin documents currently
known to refer to the rabbi of Girona. While they all identify the individual
in question as a rabbi, one of them calls him Moses and others Bonastruc de Porta,
and some do not name him at all. Particular emphasis is placed on a recently discovered
document from 1271, which mentions a son of Bonastruc de Porta, from Girona,
who enjoyed the protection of Princess Berengaria of Castile. On that basis, the
identity of Bonastruc de Portas son tallies with that of the recipient of the famous
moral letter that Moses ben Nahman sent to a son of his who lived in the court of the
King of Castile.
With an identity between Moses ben Nahman and Bonastruc de Porta established
through documentation, the article proceeds to present other historical supporting
data. Its final section casts light on the nature of the rabbis relationship with King
James I of Aragon.
The aforementioned Latin documents are set out in the appendix to the article.