Our faith in Christ needs to be fed in order to live. We need to drink the pure spiritual milk of God's Word, to hear the forgiveness of our sins, to receive the Sacrament of Christ's body and blood, otherwise our newborn faith will shrivel and die of starvation. Faith in Christ feeds on Christ. It nurses on His Word, His forgiveness, His Supper. Faith hungers and thirsts for Christ's righteousness.
Faith is like a thirsty deer, panting for a cool mountain stream of refreshing water.
Faith is like a beggar with empty hands outstretch seeking mercy. Faith is like dry, parched earth that eagerly soaks up the rain that falls on it. Faith is like a hungry newborn craving the pure spiritual milk of its mother. Faith in Christ craves the pure spiritual milk of its mother, holy Church, and the rich forgiveness, life, and salvation that come in the Name of Jesus through the Word preached and through the Sacrament. When Peter preached to the people who were gathered at the temple for evening prayer, he promised refreshment in the Name of Jesus.