When an infant eats physical food he connects to his father, as the Sages (Brachos 40a) say: “An infant does not know how to call out ‘Abba, Abba’ until he tastes the taste of grain.”
When a child calls his father, he does not do so because he understands what a “father” is, but simply because he is connected to his father. Similarly, through eating matzah a person connects to his “Father in Heaven,” even if he does not understand it intellectually.
(Lekutei Torah, Tzav)