Water is refreshing, cleansing, and clear, so it’s easy to understand why so many cultures and religions use water for symbolic purification. Washing hands twice during our Seder: now, with no blessing, to get us ready for the rituals to come; and then later, with a blessing, preparing us for the meal.
Baruch atah Adonai, Eloheinu melech ha-olam, asher kidshanu b’mitzvotav vitzivanu al n’tilat yadayim.
Blessed are You, God, Spirit of the Universe, who has sanctified us with Your commandments, and commanded us concerning the washing of the hands.