Isagoge in canonicas septem epistolas, qua (ut in Paulinis) compositionis oeconomia, et germana dispositio monstratur

INTRODUCTION

salem met, as it is in Galatians chapter 1, where he says he saw no other Apostle besides James, the brother of the Lord.
Furthermore, he is called the brother of the Lord because
he was the son of Mary of Cleophas, who was the sister
of Mary the Virgin, and in the manner of the scriptures, those are called brothers who were actually cousins. This, as it appears, is the most truthful opinion
concerning the author of the present epistle. I am not unaware, meanwhile, that it pleases some more
that this James is not of the rank of the Apostles, but of the number of the seventy
disciples, and that he is the one whom they call James of Obalia. But these are only probable conjectures, and they are worth no more than the superior reasons, and
because by this opinion much is lost
from the authority of the epistle, the former is more pleasing, so that it may be both Apostolic and catholic. From this it can be understood why the ancients called it catholic together with the following ones, because, namely, it was not written to one private