Our Lord Jesus Christ instituted the Church with his death on the cross. When we die and rise with Him, in Baptism and through daily works of repentance, we become saints in the Holy Church. In this sense the Church is our mother and she has given birth to us through her womb, in the Baptism.
Gambero, L., 1999. Mary and the Fathers of the Church 1st ed. Translated by Buffer, T., San Francisco: Ignatius Press.