The communal wedding ring was a real Jewish relic owned by a rabbi who survived the Holocaust. In fact, the rabbi had used it to wed two of writer/producer Howard Gordon's friends.
When writing the script, Howard Gordon had the characters who beat and killed Isaac as African-Americans. Gordon found anti-Semitism among black people to be an interesting subject, informed by figures such as Louis Farrakhan as well as the 1991 riots in the Crown Heights area in which a Jewish man was killed. However, Fox executives were uncomfortable with this idea because they found that African-Americans had begun watching the show in larger numbers and asked Gordon if he would turn the villains into white neo-Nazis. Gordon agreed to do so, and the network okayed the script.
The idea of a "golem," a manipulable soldier made out of magically animated mud or clay created to protect Jews during pogroms or other times of antisemitism, actually is a part of European-Jewish folklore and mythology. The earliest-known written description of a golem's creation dates from the late 1100s or early 1200s. The most famous version of the golem myth comes from 16th-Century Prague, where a Rabbi named Judah Loew ben Bezalel was fabled to have created a golem to protect Prague's Jews from pogroms. The vast majority of Jewish scholars, even strictly Orthodox ones, see the golem story as a piece of allegorical folklore and not something to be taken seriously in a religious context.
Curt Brunjes tells Mulder "you look like you might be one yourself" when he suspects that Mulder is Jewish. Both of David Duchovny's paternal grandparents were Jewish immigrants, and his father, Amram Ducovny, was a publicist for the American Jewish Commitee and the Combined Jewish Philanthropies. His mother was a Lutheran immigrant from Scotland.