in order to celebrate a vigil. These are given in an appendix of the book of the Liturgy of the Hours. To those who find it seriously difficult, because of their advanced age or for reasons peculiar to them, to observe the revised Liturgy of the Hours Pope Paul VI gave permission to keep using the previous Roman Breviary either in whole or in part. In 2007 Pope Benedict XVI allowed all clergy of the Latin Church to fulfil their canonical obligations by using the 1961 Roman Breviary issued under Pope John XXIII (but not earlier editions such as that of Pius X or Pius V). This is done by traditionalist Catholic communities, such as the Priestly Fraternity of St. Peter and the Institute of Christ the King Sovereign Priest. Non-Roman Western Rites In the office of the Church of Jerusalem, of which the pilgrim Ætheria gives us a description, the vigils on Sundays terminated with the solemn reading of the Gospel, in the Church of the Holy Sepulchre. This practice of reading the Gospel has been preserved in the Benedictine liturgy. In the Tridentine Roman Liturgy this custom, so ancient and so solemn, was no longer represented but by the Homily; but after the Second Vatican Council it has been restored for the celebration of vigils. The Ambrosian Liturgy, better perhaps than any other, preserved traces of the great vigils or pannychides, with their complex and varied display of processions, psalmodies, etc. The same liturgy also preserved vigils of long psalmody. This nocturnal office adapted itself at a later period to a more modern form, approaching more and more closely to the Roman liturgy. Here too were found the three nocturns, with Antiphon, psalms, lessons, and responses, the ordinary elements of the Roman matins, and with a few special features quite Ambrosian. As revised after the Second Vatican Council, the Ambrosian liturgy of the hours uses for what once called matins either the designation "the part of matins that precedes lLauds in the strict sense" or simply "office of readings". Its structure is similar to that of the Roman Liturgy of the Hours, with variations such as having on Sundays three canticles, on Saturdays a canticle and two psalms, in place of the three psalms of the other days in the Ambrosian Rite and of every day in the Roman Rite. In the Mozarabic liturgy, on the contrary, Matins