Pope Adrian II, Epistle to King Lothar, 867 A.D.: “For Our Lord thrice commended to blessed Peter, Prince of the Apostles, His sheep, that is to say, the whole Church, yet as then redeemed by His precious blood, after the bonds of His Passion, after the wounds of His nails, and the derisions of the cross, as also the glory of the resurrection, saying: ‘Feed my sheep; feed my lambs.’ (Jn. 21.)”