The Joyful Mysteries are those events at the beginning of the life of Christ:
- The Annunciation of the Archangel to Mary
- The Visitation of Our Lady to St Elizabeth
- The Nativity of Our Lord
- The Presentation of Our Lord in the Temple
- The Finding of Christ teaching among the Elders in the Temple
Each one of these represents a direct interplay between Our Lady and Our Lord. These are called Joyful because of the deep joy they signified to Mary, but also to us! The joys of Lady Day in March and Christmas in December, of Candlemas
The first two can seem as if Christ is very passive, but it should never be forgotten that Christ is God in the Flesh: he is never passive, no matter how it may seem to us. But he is never over-ruling either. Mary was asked if she would partake of this joy and she consented. Likewise in the Visitation, it was Christ who made the Forerunner leap for joy, but it was at his Mother's actions and words.
His actions for our salvation have been the divine plan of the ages. Fr John Behr says that Protestantism can make it sound like God made the world, man messed it up, and Christ's Life, Death, and Resurrection are a sort of "Plan B". But God knew from the beginning, from before the beginning how Man's freedom would take him away: the Mysteries of the Incarnation were always there, waiting for Man's freedom to be ready to participate in the Divine Dance: that's the Orthodox Doctrine of Synergy. We are saved in a dance with God, not by "following your bliss" or by "submission" to a divine override, but by participation.
The Joyous Mysteries are the revelation of the Dance. All of Creation from "let us make..." to "it is finished" were the opening measures of it. Praying the Rosary will draw you in to the same dance by letting you hear the same music.