Kashrut (also kashruth or kashrus, כַּשְׁרוּת) is the set of Jewish dietary laws. Food that may be consumed according to halakha (Jewish law) is termed kosher in English, from the Ashkenazi pronunciation of the Hebrew term kashér (כָּשֵׁר), meaning "fit" (in this context, fit for consumption). Food that is not in accordance with Jewish law is called treif (Yiddish: טרײף or treyf, derived from Hebrew טְרֵפָה trēfáh). Kosher can also refer to anything that is fit for use or correct according to halakha, such as a hanukiyah (candelabra for Hannukah), or a sukkah (a Sukkot booth). The word kosher has become English vernacular, a colloquialism meaning proper, legitimate, genuine, fair, or acceptable.

Among the numerous laws that form part of kashrut are the prohibitions on the consumption of unclean animals (such as pork and most insects, with the exception of crickets and locusts), mixtures of meat and milk, and the commandment to slaughter mammals and birds according to a process known as shechita. Most of the basic laws of kashrut are derived from the Torah's Books of Leviticus and Deuteronomy. Their details and practical application, however, is set down in the oral law (eventually codified in the Mishnah and Talmud) and elaborated on in the later rabbinical literature. While the Torah does not state the rationale for most kashrut laws, many reasons have been suggested, including philosophical, practical and hygienic.

In the Book of Exodus, the Book of Leviticus and the Book of Numbers, Nadab (Hebrew: נדב, Nadabh ; "generous, giving") and Abihu (Hebrew: אביהוא, Abhihu ; "He (Yahweh) is my father") were respectively the eldest and second-eldest of the sons of Aaron. They offered a sacrifice with unauthorized fire before the LORD, disobeying his instructions. Nadab and Abihu were consumed immediately by God’s fire. They trespassed upon a task that belonged only between God and the high priest. The priests were commanded not to mourn, but the people at large were permitted.

Nadab and Abihu were the first two sons of Aaron the Levite by his marriage to Elisheba. He had four sons in total, the younger two sons being named Eleazar and Ithamar. According to the book of Exodus, Aaron and his sons were the first priests appointed as the priestly system was established by God. The Levites as a tribe were later ordained for the priestly service after answering a call to take the LORD’s side after the idolatry centered around the golden calf. After the death of Nadab and Abihu, Eleazar and Ithamar took their places as priests, because neither Nadab nor Abihu had any sons.

Howard Allan Stern (born January 12, 1954) is an American radio personality, television host, author, actor and photographer best known for his radio show which was nationally syndicated from 1986 to 2005. He gained wide recognition in the 1990s where he was labeled a "shock jock" for his outspoken and sometimes controversial style. Stern has been exclusive to Sirius XM Radio, a subscription-based satellite radio service, since 2006. The son of a former recording and radio engineer, Stern wished to pursue a career in radio at the age of five. While at Boston University he worked at the campus station WTBU before a brief stint at WNTN in Newton, Massachusetts.

He developed his on-air personality when he landed positions at WRNW in Briarcliff Manor, WCCC in Hartford and WWWW in Detroit. In 1981, he was paired with his current newscaster and co-host Robin Quivers at WWDC in Washington, D.C. Stern then moved to WNBC in New York City in 1982 to host afternoons until his firing in 1985. He re-emerged on WXRK that year, and became one of the most popular radio personalities during his 20-year tenure at the station. Stern's show is the most-fined radio program, after the Federal Communications Commission (FCC) issued fines to station licensees for allegedly indecent material that totaled $2.5 million. Stern has won Billboard's Nationally Syndicated Air Personality of the Year award eight times, and is one of the highest-paid figures in radio.