16 To ward off these exceedingly great dangers of ignorance from her children, the Church, which never relaxes her vigilant and diligent care, has been in the habit of looking for the stanchest support of faith in the Rosary of Mary. And indeed in the Rosary, along with the most beautiful and efficacious prayer arranged in an orderly pattern, the chief mysteries of our religion follow one another, as they are brought before our mind for contemplation: first of all the mysteries in which the Word was made flesh and Mary, the inviolate Virgin and Mother, performed her maternal duties for Him with a holy joy; there come then the sorrows, the agony and death of the suffering Christ, the price at which the salvation of our race was accomplished; then follow the mysteries full of His glory; His triumph over death, the Ascension into heaven, the sending of the Holy Spirit, the resplendent brightness of Mary received among the stars, and finally the everlasting glory of all the saints in heaven united with the glory of the Mother and her Son.
Source: Magnae Dei Matris (Vatican.va)