Must all the mysteries be prayed to gain the rosary indulgence?
The short answer
No. Five decades are enough. A plenary indulgence is granted for the rosary prayed in a church, oratory, family, religious community or pious association, without interruption and with meditation on the mysteries; otherwise the indulgence is partial.
Only five decades are needed for a partial or plenary indulgence. The Handbook of Indulgences says:
- A plenary indulgence is granted when the rosary is recited in a church or oratory, or in a family, religious community or pious association; a partial indulgence in all other circumstances.
- One set of five mysteries, customarily called "the rosary," suffices for the plenary indulgence, but the five decades must be prayed without interruption, with devout meditation on the mysteries added to the vocal prayer.
- In public recitation the mysteries must be announced according to approved local custom; in private, it is enough to join meditation to the vocal prayer.
- In Eastern Churches without the rosary, patriarchs may establish other Marian prayers with the same indulgences, such as the Akathist hymn or the Paraclisis in the Byzantine churches.
Canon 996 adds that to gain indulgences one must be baptized, not excommunicated, and in the state of grace at least at the end of the prescribed works, and must have at least a general intention of gaining them and perform the works at the time and in the manner required. See also Paul VI's Indulgentiarum Doctrina.