“What birth according to the flesh could be more fitting for God than this one, in which the immaculate Son of God, even in assuming a body, should maintain the purity of an immaculate birth? Surely the sign of the divine event consists in his being born of a virgin, not from a woman?”Ambrose of Milan, Expositio in Lucam 2, 78; PL 15, 1663.
Gambero, L., 1999. Mary and the Fathers of the Church 1st ed. Translated by Buffer, T., San Francisco: Ignatius Press.