In the words of the Second Vatican Council

(The Dogmatic Constitution on the Church, Lumen Gentium 63-65)

For in the mystery of the Church, which is called mother and virgin, the Blessed Virgin eminently stands out as exemplar both of Virgin and Mother. By her belief and obedience, not knowing man but overshadowed by the Holy Spirit, [she is] the New Eve who brought forth on earth the Son of the Father…. The Son whom she brought forth is He whom God placed as the first-born among many brothers and sisters – namely the faithful – in whose birth and education she cooperates with a maternal love.

The Church indeed, contemplating her hidden sanctity, imitating her charity, and faithfully fulfilling the Father's will, by receiving the word of God in faith becomes herself a mother. By her preaching she brings forth a new and immortal life to her children, who are born to her in Baptism, conceived of the Holy Spirit, and born of God. She herself is a virgin, who keeps the faith given to her by her Spouse, whole and entire. Imitating the Mother of her Lord, and by the power of the Holy Spirit, [the Church] keeps with virginal purity an entire faith, a firm hope, and a sincere charity.

But while, in the most holy Virgin, the Church has already reached that perfection whereby she is “without spot or wrinkle”, the followers of Christ still strive to increase in holiness by conquering sin. So, they turn their eyes to Mary, who shines forth to the whole community of the elect as the model of virtues. Piously meditating on her and contemplating her in the light of the Word made man, the Church reverently enters more intimately into the great mystery of the Incarnation and becomes more like her Spouse. For Mary, who since her entry into salvation history, unites in herself and re-echoes the greatest teachings of the faith as she is proclaimed and venerated, calls the faithful to her Son and His sacrifice and to the love of the Father. Seeking after the glory of Christ, the Church… progresses in faith, hope, and charity, seeking and doing God’s will in all things. Hence the Church… looks to her, who…brought forth Christ, who…through the Church He may be born and may increase in the hearts of the faithful.