I. The designs of the devil have led Eutyches astray.
To the most holy and God-loving father and fellow bishop, Leo, Flavian greeting in the Lord.
There is nothing which can stay the devil's wickedness, that “restless evil, full of deadly poison.” Above and below it “goes about,” seeking “whom it may” strike, dismay, and “devour.” Whence to watch, to be sober unto prayer, to draw near to God, to eschew foolish questionings, to follow the fathers and not to go beyond the eternal bounds, this we have learned from Holy Writ. And so I give up the excess of grief and abundant tears over the capture of one of the clergy who are under me, and whom I could not save nor snatch from the wolf, although I was ready to lay down my life for him. How was he caught, how did he leap away, hating the voice of the caller and turning aside also from the memory of the Fathers and thoroughly detesting their paths. And thus I proceed with my account.
Source: Letters (New Advent)