Augustine of Hippo

Who then is so just and holy a priest as the only Son of God, who had no need of a sacrifice for the washing away of his own sins, neither original sins nor those that are added from human life? And what could be so fittingly chosen by men to be offered for them as human flesh? And what so suitable for this immolation as mortal flesh? And what so clean for cleansing the vices of mortals as the flesh born in the womb without the contagion of carnal concupiscence, and coming from a virginal womb? And what could be so acceptably offered and received as the flesh of our sacrifice made the body of our priest? Four things are to be considered in every sacrifice: by whom it is offered, to whom it is offered, what is offered, and for whom it is offered.