The fourth perek of Massekhet Shekalim, which begins on our daf opens with the question of how the shekalim are spent. We have already noted that the communal sacrifices were purchased with this money, but there were other needs in the Temple and in Jerusalem that were paid for with these donations. For example, our Gemara teaches that the sages who taught the rules of the Temple service to the kohanim were paid with this money.
Tosafot in Ketubot (105b) points out that paying people who teach Torah is not a simple thing, and, in theory, should be forbidden entirely. The only payment that a teacher can receive is sekhar batala – the value for his time that he could have spent on more lucrative endeavors. Another arrangement that can be made is a stipend to be paid to a scholar who agrees that he will not be involved in any business activities whatsoever so that they will always be available for the needs of the community. According to Rabbi Vidal Crescas, this is the method that is popularly used to pay community Rabbis to this day. The Rambam in Hilkhot Talmud Torah 3:9-10 takes a strong stand on this issue, forbidding scholars from receiving payment in exchange for Torah study, although the Kesef Mishneh (ibid) rules even the Rambam would agree that it would be permissible if the scholar serviced the needs of the community.
It should be noted that in previous times people literally lived hand-to-mouth and there was very little leisure time, making it almost impossible to divide time between learning Torah and working. In our day-and-age, arranging one’s work environment so that it is possible support oneself and study Torah is a strong possibility.
One of the examples of what was taught is the rules of kemitza. Kemitza involved taking an exact amount of the flour for the meal offering in one’s hand, and it was very difficult to ensure that the exact amount was taken. A similar lesson that needed to be taught was the rule regarding melika, the unique manner in which the sacrificed fowl was slaughtered. This was known as one of the most difficult of the Temple services, and Tosafot argues that this, too, needed to be taught to the kohanim by experts. Since every group of kohanim that came to the Temple to work needed to learn and to review these laws, there was constant work for those scholars who knew how to teach this material.