What's a Motu Proprio?

Pope Benedict XVI will be issuing an apostolic letter entitled Sacramentum Caritatis (Sacrament of Charity) Tuesday morning (3/13/2007) at 7 a.m. The title continues B16's focus on love; his first papal encyclical was Deus Caritas (God Is Love). This appears to be a very carefully written letter, as it has been in the works since the end of the 11th Ordinary General Assembly of Bishops, a Synod on the Eucharist that took place in October, 2005.

This apostolic letter is in the form of a 'Motu Proprio'. Condensing from the Catholic Encyclopedia entry, a motu proprio is a papal letter written 'of [the Holy Father's] own accord', without seal or counter-signature, allowing the Pope to to instruct in his own words, without consulting the advice of cardinals or others.

Evidently, the Vatican has successfully embargoed this text to prevent early publication or leaks. This, perhaps, explains the lack of coverage in the mainstream press. Interested web sites are buzzing with speculation about reforms the Holy Father may encourage, or the possibility that use of the Mass from the (pre-Vatican II) 1962 Missale Romanum (the 'Tridentine Mass') may be liberalized or even encouraged.

Whatever the letter contains, Pope Benedict's preferences for liturgy and music are already well-documented. I hope the same love he's selected as the theme for his encyclical and apostolic letter is applied by the Church and used by the faithful to encourage appreciation for all things holy, beautiful, and true. Veni, Sancte Spiritus.

UPDATE - Here is the Motu Proprio.