20 Abuses like these were bitterly lamented by the great men of the time, such as Lanfranc, Anselm's master and later his predecessor in the see of Canterbury, and still more by the Roman Pontiffs, among whom it will suffice to mention here the courageous Gregory VII, the intrepid champion of justice, unswerving defender of the rights of the Church, vigilant guardian and defender of the sanctity of the clergy.
Source: Communium Rerum (Vatican.va)