For there is one God, and there is one mediator between God and men, the man Christ Jesus, who gave himself as a ransom for all, the testimony to which was borne at the proper time.The practice is witnessed to by Justin Martyr and Augustine of Hippo, and by the fourth century, the Roman Rite had a set of nine Solemn Prayers of Intercession of the kind now preserved only in the Good Friday at the same point of Liturgy at which the ordinary General Intercessions are prayed.
[1] The General Intercessions dropped out of use, leaving only the introductory greeting "Dominus vobiscum" and the invitation "Oremus" (followed by no particular prayer) that in the Tridentine Mass the priest said when about to begin the Offertory.
They were one of the elements that the Second Vatican Council referred to when decreeing in Sacrosanctum Concilium, 50: "Other parts which suffered loss through accidents of history are to be restored to the vigour they had in the days of the holy Fathers, as may seem useful or necessary".
It is fitting that such a prayer be included, as a rule, in Masses celebrated with a congregation, so that petitions will be offered for the holy Church, for civil authorities, for those weighed down by various needs, for all men and women, and for the salvation of the whole world.
A deacon, another member of the congregation, or the priest himself recites a number of intentions, and the people respond with a short invocation such as "Lord, hear our prayer."