Before the Seder, one must prepare the Seder plate, on which all of the special Seder foods are arranged. Setting the Seder plate is not merely to keep the foods close by and at the ready, but also because each food commemorates and emphasizes a particular idea, and we must keep all the foods in front of us to express the uniqueness of the Seder. These foods are placed on the Seder plate:
Three matzot with which we fulfill the Torah’s commandment to eat matza. We place them on the Seder plate so we can recite the Hagada in the presence of matza and maror, fulfilling the verse, “Tell your child on that day: ‘It is because of this that God did for me when I left Egypt’” (Shemot 13:8), which the Sages interpret: “‘because of this’ means when matza and maror are before you” (Mekhilta Bo 17). Additionally, matza is called “leḥem oni” – “poor man’s bread” (Devarim 16:3) – which the Sages interpret to mean “bread over which we ‘onim’ – answer or say – many things.” The matza must therefore be uncovered while we recite the Hagada. However, out of respect for the matza, which is the most important food on the table and over which we recite the “ha-motzi” blessing, we do not recite kiddush while the matza is uncovered. Therefore, we cover the matzot during kiddush and when we lift our wine glasses, but otherwise they remain exposed while we recite the Hagada.
Maror is lettuce or horseradish. When the Temple stood, there was a Torah commandment to eat maror with the korban Pesaḥ, but since the destruction of the Temple, the mitzva to eat maror is rabbinic.
In Temple times, the meat of the korban Pesaḥ was also put on the Seder table, but with the Temple’s destruction, the Sages enacted that two cooked foods be placed on the table: one to commemorate Paschal sacrifice, and the other to commemorate the korban ḥagiga (pilgrimage sacrifice), offered on every pilgrimage festival (Pesaḥim 114a-b). Customarily, the Paschal sacrifice is commemorated with a zero’a, alluding to the fact that God redeemed us with an “outstretched arm” (“zero’a netuya”). We roast the zero’a, just as the Paschal sacrifice was roasted. Sephardic Jews customarily use the foreleg of a lamb or goat, whereas Ashkenazim use the wing of a fowl. The korban ḥagiga is customarily commemorated with a roasted or boiled egg. Eggs are customarily served to mourners, as their round shape consolingly reminds them of life’s cyclical nature. At the Seder, the egg similarly reminds us that the Temple will be speedily rebuilt and we will again be able to offer the Paschal and ḥagiga sacrifices. Additionally, the Aramaic word for egg, “bei’a,” means “supplication,” alluding to our request of God to redeem us once again (SA 473:4). The custom in most communities is not to eat the zero’a on the Seder night (see below, section 32).
We also place karpas and either vinegar or salt water on the Seder plate. Karpas is the vegetable that we eat before reciting the Hagada. It is dipped in vinegar or salt water both to make it tastier and to create the need for an additional hand-washing, which causes the children to ask more questions.
We place ḥaroset on the Seder plate as well. Ḥaroset alludes to the clay mortar our forefathers made when they were enslaved in Egypt. Before eating the maror, we dip it in the ḥaroset.
Wine is not placed on the Seder plate because it is a drink, not a food.