"Following the first announcement of the next extraordinary Holy Year by Pope Francis on March 13th, the Holy Father will proceed with the official indiction of the Jubilee of Mercy with the publication of the Bull of Indiction on Saturday 11 April, at 5.30 pm in St. Peter’s Basilica."

So indicates a communique released by the Holy See Press Office, which said that "the rite of publication will involve the reading of various passages of the Bull before the Holy Door of the Vatican Basilica."

The Pope will preside over the celebration of Vespers on the eve of Divine Mercy Sunday which, according to the communique, underlies "in a particular way the fundamental theme of the extraordinary Holy Year: God’s Mercy."

"The term bull (from the Latin bulla = bubble or, more generally, a rounded object) – the note continues - originally indicated the metal capsule used to protect the wax seal attached with a cord to a document of particular importance, to attest to its authenticity and, as a consequence, its authority."

"Over time, the term began to be used first to indicate the seal, then the document itself, so that nowadays it is used for all papal documents of special importance that bear, or at least traditionally would have borne, the Pontiff’s seal."

The note from the Holy See Press Office concluded, explaining that the bull for the indiction of a jubilee "constitutes the fundamental document for recognizing the spirit in which it is announced, and the intentions and the outcomes hoped for by the Pontiff, who invokes it for the Church."

The last extraordinary Holy Year was declared by St. John Paul II in 1983, which commemorated the 1,950thanniversary of the Year of Redemption: the year of Christ's death. (J.A.E.)