12 In short, we may see how great an evil in itself is envy, which cannot be other than malicious. Let us not look for other testimony. Cyprian himself is sufficient for us, through whose mouth the Lord poured forth so many thunders in most perfect truth, and uttered so many useful precepts about envy and malignity. Let us therefore read the letter of Cyprian about envy and malignity, and see how great an evil it is to envy those better than ourselves—an evil whose origin he shows in memorable words to have sprung from the devil himself.
"To feel jealousy," he says, "of what you regard as good, and to envy those who are better than yourselves, to some, dearest brethren, seems a light and minute offense." And again a little later, when he was inquiring into the source and origin of the evil, he says, "From this the devil, in the very beginning of the world, perished first himself, and led others to destruction." And further on in the same chapter: "What an evil, dearest brethren, is that by which an angel fell!
By which that exalted and illustrious loftiness was able to be deceived and overthrown! By which he was deceived who was the deceiver! From that time envy stalks upon the earth, when man, about to perish through malignity, submits himself to the teacher of perdition,— when he who envies imitates the devil, as it is written, 'Through envy of the devil came death into the world, and they that do hold of his side do find it.'" How true, how forcible are these words of Cyprian, in an epistle known throughout the world, we cannot fail to recognize.
It was truly fitting for Cyprian to argue and warn most forcibly about envy and malignity, from which most deadly evil he proved his own heart to be so far removed by the abundance of his Christian love; by carefully guarding which he remained in the unity of communion with his colleagues, who without ill-feeling entertained different views about baptism, while he himself differed in opinion from them, not through any contention of ill will, but through human infirmity, erring in a point which God, in His own good time, would reveal to him by reason of his perseverance in love.
For he says openly, "Judging no one, nor depriving any of the right of communion if he differ from us. For no one of us sets himself up as a bishop of bishops, or by tyrannical terror forces his colleagues to a necessity of obeying." And in the end of the epistle before us he says, "These things I have written to you briefly, dearest brother, according to my poor ability, prescribing to or prejudging no one, so as to prevent each bishop from doing what he thinks right in the free exercise of his own judgment.
We, so far as in us lies, do not strive on behalf of heretics with our colleges and fellow bishops, with whom we hold the harmony that God enjoins, and the peace of our Lord, especially as the apostle says, 'If any man seem to be contentious, we have no such custom, neither the churches of God.' Christian love in our souls, the honor of our fraternity, the bond of faith, the harmony of the priesthood, all these are maintained by us with patience and gentleness. For this cause we have also, so far as our poor ability admitted, by the permission and inspiration of the Lord, written now a treatise on the benefit of patience, which we have sent to you in consideration of our mutual affection."
Source: On Baptism, Against the Donatists (New Advent)