The very first canonical hour of the new liturgical year is a wonderful moment ... to begin praying the Office, the Roman Breviary (or the traditional Breviaries of different orders and uses of the Latin Church).
Do you have a Breviarium Romanum published between 1912 and 1960, but are not sure of how to use it according to the 1960 rubrics? The Variationes, published together with the 1960 Codex Rubricarum, make your life quite easy: we make them available to you in a printable version of the original Latin text (provided by Mr. Laszlo Kiss, R.I.P.). The changes are available in English from page 118 of the excellent translation and commentary by Fr. Patrick Murphy, made public by the FSSP Sydney Latin Mass Community. And do not forget this particular source: Divinum Officium, which may be of great help.
