"Trust in HaShem is the single most important requirement needed to serve HaShem" (Duties of the Heart). This concise statement is a spiritual sun that illuminates the path of Torah and Mitzvot. Trust in HaShem is the key factor that leads to spiritual success, and it is infinitely more important than intelligence, effort, wealth, or status! For example, the trust in HaShem of our holy Avot, Avraham, Yitzchak, and Yaacov, granted them the knowledge of the entire Torah, even before HaShem revealed the Torah on Mount Sinai. In light of this, every person, regardless of his challenges, has the opportunity to excel in serving HaShem. The more we strengthen our trust in HaShem, the more we are empowered to advance in our service of HaShem.
Spirituality is like the flight of a bird. As long as the bird flaps his wings he ascends to heaven, yet when he makes no effort to climb upwards he descends. So too, as long as we strengthen our trust in HaShem, the closer we come to HaShem and the more joy we experience.
Envision Avraham Avinu as a young child living in a society of pagans. See him contemplate on the universe and recognize the kind Creator. Each day he strengthens his faith and trust in HaShem a little more. Ultimately, he emerges with towering, unshakeable faith in HaShem. In return for his extraordinary faith, HaShem blesses him boundless blessings. He merits to be the progenitor of Klal Yisrael, a Prophet, and the innovator of loving kindness.
(Based on Chovot HaLevavot)