“Throughout this month of May, let us offer our pleas to the Mother of God with greater devotion and confidence, so that we may obtain her favor and her blessings. Even if the grave sins of men provoke God’s justice and merit His just punishments, we must not forget the he is “the Father of mercies and the God of all comfort,” that He has appointed Mary most holy as the generous steward of His merciful gifts.

May she who experienced the cares and hardships of earthly life, the weariness of daily toil, the hardships and trials of poverty, and the sorrows of Calvary, come to aid the needs of the Church and the human race. May she graciously lend an ear to the devout pleas of those all over the world who beg her for peace. May she enlighten the minds of those who rule nations. And finally, may she prevail on God, who rules the winds and storms, to calm the tempests in men’s warring hearts and grant us peace in our day. What we seek is true peace grounded on the sturdy foundations of justice and love—on a justice which recognizes the legitimate rights of the weak as well as those of the strong; on a love which keeps men from falling into error through excessive concern for their own interests. Thus each person’s rights may be safeguarded without the rights of others being forgotten or violated.”

— Pope Paul VI, Mense Maio,
his encyclical on prayers during May for the preservation of peace, issued in 1965.