What is the reason for wearing the white “kittel” at the Seder table on Passover night? Since we wear our festive best during the prayers, what’s the reason for changing into this relatively simple garment for the Seder?
Although it is a mitzva to adorn oneself on this night with costly garments to demonstrate our liberty, according to the Ashkenazic custom, at the meal it is customary for adult males to wear the simple white robe-like garment called a “kittel” in Yiddish.
One of the reasons for this is that since the dead are buried in white shrouds, wearing this robe reminds one of his mortality and curtails any excessive pride that might result from one’s newly-gained “liberty”. We find a similar idea regarding eating the hard-boiled egg at the Seder, which is a symbol of mourning and thus a warning against pride.
Alternatively, these symbols of mourning are related to the fact that Tisha b’Av, the day of mourning over the destruction of the Temple, always occurs on the same day of the week as Passover.
However, other commentators explain the custom of wearing the kittel in a different light. They maintain that there is nothing finer than a plain white garment. For it was thus that the Cohen Gadol, or High Priest, entered the innermost sanctuary on the holiest of days for the most elevated of services – the offering of incense before the holy Ark of the Covenant. On this night, each head of family who celebrates the sacred Seder is like the Cohen Gadol performing the service of G‑d in the Holy of Holies!