Chazal instituted netilas yadayim both upon waking up in the morning and before eating bread. Varied explanations are offered for the morning washing, including cleansing one’s hands from dirt (Rosh) and to remove negative spirits after having been “recreated” (Rashba). It is also a rabbinic mitzvah to wash one’s hands before a bread meal, enacted to maintain the practices of terumah eaten by the kohanim. In order to remove the impurity of his hands so that the terumah would not become defiled, a kohen would wash his hands with water. Even a non-kohen, eating a non-“holy bagel,” would wash to insure the kohen did as well.
Additionally, netilas yadayim is a practice of holiness and cleanliness performed by kohanim before their service in the Beis HaMikdash. As our table is comparable to the Altar, and our bread like an offering brought on the Altar, we wash our hands before eating bread and thereby sanctify our eating. Personally, netilas yadayim throughout the day creates mindfulness of cleanliness and nostalgia for the Beis HaMikdash to be rebuilt speedily in our days.
