Fr. Z posts the entire text of Paul VI's Apostolic Constitution promulgating the new Missal of 1969.
It's very interesting to read it, and Fr.'s commentary is hilarious and informative. But I'm particularly struck by this passage from Paul VI, which seems to have been completely overlooked:
The text of the Graduale Romanum has not been changed as far as the music is concerned. In the interest of their being more readily understood, however, the responsorial psalm (which St. Augustine and St. Leo the Great often mention) as well as the entrance and communion antiphons have been revised for use in Masses that are not sung.
