Here the lilies stand for Christ, and the grain is the faithful. As Virgin Mary gave birth to Jesus Christ, she became the “Mother” of all men on a spiritual level. She participates in building the Church into the body of Christ. On the personal level, each believer can participate in building the Church. Believers can work with Holy Spirit by working on living a life of holiness, which brings the fruits of love, joy and peace. When others see this they join the Church.
Gambero, L., 1999. Mary and the Fathers of the Church 1st ed. Translated by Buffer, T., San Francisco: Ignatius Press.