Hebrews or Israelites are the ancestors of the Jews and Samaritans and the eponym of Israel - where they've lived since at least the 13th Century BC. The Hebrews are the source of the Biblical stories that led to the creation of the other Abrahamic monotheistic religions.
The Hebrews are first mentioned in the franchise's pilot, "Cartman Gets an Anal Probe" (also in the "The Unaired Pilot"), when Mr. Hat claims that "Columbus discovered America and was the Indians' best friend. He helped the Indians win their war against Fredrick Douglass and a freed the Hebrews from Napoleon and discovered France".
The Hebrews' tradition of circumcision is the subject of "Ike's Wee Wee".
The Hebrews are mentioned again in "Mr. Hankey, the Christmas Poo", where Sheila Broflovski mentions that Hannukah is a very important holiday and event for the Hebrew People in the song "Dreidel, Dreidel, Dreidel", and where Kyle sings his song, "The Lonely Jew on Christmas", about being culturally and ethnically different from his friends who celebrate Christmas while his family celebrates Hannukah.
The teachings of the Hebrews are allegedly being taught by the scouts in the Jewish Camp, Kyle and Ike Broflovski attend to, where the kids are making pasta images for Moses' amusement as seen in "Jewbilee". It is shown that the Hebrew scouts' elders and Moses are suspicious of children who are not truly of Hebrew descent, yet are converts to Judaism as seen with one Asian descent kid who was sent out of the room; however they had no problems with Kenny McCormick at first look - probably because he's white as well. Garth, of the synagogue of anti-Semites, is an enemy of the modern American Hebrews as he tries to summon Haman who by the 5th Century BC tried to exterminate all the Jews in the Persian Empire, to fulfil his goal - however Kenny and the Jewish scouts prevented that.
In "Free Hat", Steven Spielberg can be seen dressed as the Hebrews' High Priest and carrying a speech about his newly released "Raiders of the Lost Ark - Digitally Enhanced" which he hid in a trunk designed as the Ark of the Covenant that the Ancient Hebrews had in the Biblical era Jerusalem's Jewish Temple. After his movie kills everyone due to its lameness, the spirit devouring power returns to the Ark and closes it. An Ark of the Covenant prop can be seen in Michael Jackson's son's room in "The Jeffersons".
In "Jewpacabra", Sheila explains to Eric Cartman (who allegedly is interested to learn about the Jewish Holiday of Passover) about the history of the Hebrews in Ancient Egypt, which is a also touched upon within Cartman's visions later that episode as he imagines the sacrifice of the lambs requested by the Hebrews' God and the 10 Plagues that God landed on the Ancient Egyptians before the Exodus.
In "Smug Alert!", after the Broflovskis had moved to San Francisco, Cartman asks Butters Stotch to serve as Kyle's replacement in an NFL video game, and when he defeated him he make derogatory comments about Hebrews (referring to them by the name "Heebs").
In the end of "Ginger Cow", the Hasidic Jews from Israel reveal that the Hebrews' original secret and sacred prophecy was that a fat kid with a small penis would make a cow look ginger, and that it would be sacrificed for "world peace", making Kyle's 'sacrifice' entirely pointless.
In "Naughty Ninjas", Cartman mentioned that he had shared his hatred for Hebrews with the ISIS terrorist whom he believed to be an online ninjas recruiter, which they've talked long about with their different perspectives.
In "Mexican Joker", Kyle teaches the Hispanic migrants' children to say the "Shema Yisrael" prayer in the Hebrew language to pretend they've converted into Judaism, so they won't kept jailed nor get deported.
Michelangelo's depiction of King David, the Hebrews' monarch, can be seen in the Monty Python Special "Dead Friend Sketch".
- Hebrews at Wikipedia