Pius XI

Radio message to Lourdes, April 28, 1935:

O Mother of piety and mercy, who as Co-Redemptrix stood by your most sweet Son suffering with Him when He consummated the redemption of the human race on the altar of the cross ... preserve in us, we beg, day by day, the precious fruits of the Redemption and of your compassion.

Encyclical, Miserentissimus Redemptor, May 8, 1928:

May the kindly Virgin Mother of God be present and smile on these our prayers and undertakings, who, since she brought forth Jesus the Redeemer, fed Him, offered Him as a victim at the cross, by her hidden union with Christ, and an altogether singular grace from Him, was likewise the Reparatrix, and is devoutly called that.

Apostolic Letter, Explorata res est, Feb. 2, 1923:

... the sorrowful Virgin shared in the work of redemption with Jesus Christ ...