All Souls Day

"Indeed, on the day after the feast of All Saints, when the Church joyfully celebrates the communion of saints and human salvation, St Odilo (abbot of the monastery of Cluny) urged his monks to say special prayers for all the dead, thus mysteriously contributing to their entry into beatitude; the custom of solemnly interceding for the dead in a celebration which St Odilo called All Souls Day gradually spread from the Abbey of Cluny and is now the practice throughout the universal Church.

"In praying for the dead, the Church above all contemplates the mystery of the Resurrection of Christ, who obtains salvation and eternal life for us through his Cross."

John Paul II
Message for Millenium of All Souls Day, 1-2 (excerpt)
June 2, 1998