The "bitter herb" eaten with unleavened bread (Matzah) and the paschal sacrifice (pesaḥ) as part of the original meal prior to the Children of Israel's Exodus from Egypt (Ex. 12:8). The commandment was expanded to be observed by Jews "throughout the ages" (Ex. 12:7; Num. 9:10-11) and thus became a part of the Passover eve Seder ritual. In the Bible the word appears only in the plural form, merorim, but in the Talmud the singular form is noted and appears in the Haggadah. The bitter herbs are explained as symbolizing the bitterness of the Israelites' slavery in Egypt.The Talmud (Pes. 39a) discusses the characteristics of the plants which can be used for the bitter herbs, defined as those containing an "acrid [pungent] sap and faded leaves." The Mishnah (Pes. 2:5) enumerates five types of plants which can be used. They are: "lettuce (ḥazeret), chevril (tamka), succory (ḥarḥavina) or Cichorium itybus, endives (olshin), and maror." Many biologists today link the maror with a plant that grows wild in Israel and is known by the Arabic name murar. In Eastern Europe it became customary to use the horseradish root for the bitter herb.
During the Seder service itself the maror is eaten twice: once with the ḥaroset (the nut-apple mixture) to temper its bitterness and, immediately following, with the matzah in a sandwich form when the full strength of the bitterness is experienced.




