Orate, Fratres (i.e. Pray, Brethren), is the technical term of the Romanists applied to the celebrant priest's exhortation at mass when the Church is about to engage in secret prayer for God's acceptance of the sacrifice offered. It precedes the Preface (q.v.), and follows immediately after the celebrant has pronounced this prayer:
"Receive, holy Trinity, this oblation, which we offer to thee in commemoration of the suffering, resurrection, and ascension of Jesus Christ our Lord, and to the honor of blessed Mary ever Virgin, and of blessed John the Baptist, and of holy apostles Peter and Paul, and not only of those, but also of all saints; that it may profit them unto honor, but us unto salvation: and that they may deign to intercede for us in heaven; whose memory we celebrate on the earth. Through the same Christ our Lord. Amen." The celebrant then says the words "Orate, Fratres," with his voice a little elevated; but the remainder ["that my and your sacrifice may be acceptable with God the Almighty Father"] is said inaudibly, or "in a perfectly under tone." Then the priest turns round to the altar and joins his hands before his breast; and the attendant or bystanders answer, or otherwise the priest himself — "May the Lord receive the sacrifice from thy (or my) hands, to the praise and glory of his name, to our profit also, and that of all his own holy Church." The priest, with a loud voice, says "Amen." The secret prayer or prayers which follow are variable, and correspond with the collects for the day or occasion. At the conclusion of these the priest says in a distinct voice, or sings, "Per omnia scecula sceculorum" (=Through all the ages of ages, i.e. world without end); the choir answers, "Amen" the priest follows, "Dominus vobiscum" (=The Lord be with you); the response is, "it cum spiritu tuo (=And with thy spirit); the priest says, "Sursum corda" (=Lift up your hearts); and is answered, "Habemus ad Dominunm" (=We have, unto the Lord); then the priest, "Gratias agamus Domino Deo nostro" (=Let us give thanks to the Lord our God); and the choir, "Dignum etjustum est" (=It is proper and right); after which he says or sings the preface. See Barnum, Romanism as it is, p. 434.