The Divrei Chaim of Tzanz’s zt’l doctor asked him what he does. He replied, “I build bridges.” The doctor couldn’t imagine that the rabbi seated before him is an engineer. The Tzanzer Rav explained, “I’m busy building a bridge that spans between my mind and heart, so the thoughts of my mind will affect my heart.” Because the mind can know concepts, but it requires constant review until the heart also knows it.
In other words, people are often worried about the future even though they know all about emuna. This is because they know intellectually that everything is for the good, that Hashem is helping them and they can place their trust in Him, but this emuna hasn’t reached their hearts. The same was true for the Jewish people in Mitzrayim until Hashem took us out. This occurs every year anew, for on Pesach we acquire genuine emuna that reaches the heart. Rebbe Elimelech of Lizensk zt’l said that the time that is most mesugal for attaining perfection in emuna is the night of Shevi’i shel Pesach.