We know further that the demands upon them did not end there. In Palestine the organization of the Sanhedrin had maintained itself, although only in the form of several schools under the general presidency of the Nasi, whom Romans and Greeks called the Patriarch. The maintenance of these schools and those who labored in them was a religious duty which most Jews voluntarily assumed. The money was collected by _apostoli_, “envoys,” despatched to the various Jewish synagogues for that purpose.[399] The early Christian emperors believed, or professed to believe, that the payment of this tax was a grave burden to the poorer Jews, and that irregularities were committed in its enforcement. The Jewish sources, all of which are Palestinian, naturally show no trace of this complaint; nor is it likely that there was much foundation for it except in certain localities already grievously burdened by constantly increasing dues. Besides these various classes into which the tax-paying Jewish citizens fell, there were also Jews who did not share in the support of the state at all. Jewish slaves existed in the third and fourth centuries too, but they can scarcely have been numerous. A Jewish slave belonging to a Jewish master was practically only a servant bound for a term of years.[400] Within a relatively short space of time he could demand his freedom by Biblical law. If his master was a pagan, a religious duty devolved upon all other Jews, and particularly the local synagogue, to redeem him.[401] Often, to be sure, that duty could not be carried out. Not every master would sell, and not every synagogue was financially able to supply the necessary funds. In general, however, it added another motive to those already existing that made emancipations frequent. The social position and occupations of the Jews throughout the empire are only slightly known. For Egypt and Rome we have fuller documents than elsewhere, except for Babylon, which was outside the empire. We have no means of determining whether the facts found in Egypt and Rome are in any way typical. One negative statement may however be safely made. They were only to a very slight extent merchants or money-lenders. In most cases they seem to have been artisans. The inscriptions in the Jewish catacombs show us weavers, tent-makers, dyers, butchers, painters, jewelers, physicians.[402] In Egypt we meet sailors and handicraftsmen of all description.[403] Vendors, of course, on a small and large scale were not wholly lacking. Indeed it would be impossible to understand the individual prosperity of some Jews or of some communities except on the assumption of commercial occupations and success. However, in general, commerce was principally in the hands of Syrians and Greeks, especially the former, whose customs and cults spread with them over the Mediterranean.