As was noted at the end of the last perek, the korban Pesah needs to be eaten by a group of people who joined together before the holiday for the purpose of participating in the sacrifice as a group (see Shmot 12:3-5). Perek ha-Isha, the eighth chapter of Massekhet Pesahim focuses on this group. How and when is it established? Who can participate and who cannot? Under what circumstances can an individual choose to leave one group and join another? Questions such as these are the major concern of this perek.
It is not uncommon for the Gemara to segue into a discussion of aggadata after quoting passages that help clarify a topic of halakha. On our daf, after quoting pesukim (verses) from Sefer Hoshea as a proof-text for a rule in the Mishna, the Gemara brings other pesukim from that book, which leads to a discussion about the place of the Jewish people in the Diaspora.
One of the comments is made by Rabbi Oshaya, who teaches that God was being generous with the Jewish people when he dispersed them among the nations of the world, since their distribution around the world guarantees that they cannot all be threatened together.
The Gemara relates that a non-believer told Rabbi Hanina that the non-Jews were better than the Jews, since the navi tells the story of Yo’av leading the Jewish people in a six-month battle against the Edomites until they were wiped out (I 11:16), yet the non-Jews had not destroyed the Jewish people who had been living in their midst for years. Rabbi Oshaya, who was assigned to discuss the matter with him, argued that there was nothing they could do against the Jews. Those who were not in the country were out of their reach, and they could not destroy the Jews who lived amongst them, since then they would develop a reputation of killing their own citizens. The non-believer responded by swearing gappa d’Romai, that Rabbi Oshaya was correct.
Many of the commentaries weigh in on the question of defining the oath gappa d’Romai. Some say that it means a fortress and refers to the capital city of Rome. Others say that the word gappa is similar to the Hebrew kanaf – wings – and the reference is to a winged idol that “defends the city with its wings.” Another suggestion is that it is a deliberate mispronunciation of the name of the central god of the Roman pantheon – Jupiter.