OPEN O Lord, my mouth to bless Thy holy name; cleanse also my heart from all vain, perverse, and distracting thoughts; enlighten my understanding, inflame my will, that I may worthily, attentively, and devoutly recite this Office, and deserve to be heard in the presence of Thy divine Majesty. Through Christ, our Lord. R. Amen. O Lord, in union with that divine intention wherewith Thou didst offer praises on earth to God, I offer these Hours to Thee.
Hours that are said separately are preceded by the single prayer, Dómine in unión.