Nicene and Post-Nicene Fathers, Ser. II, Vol. III:
Life and Works of Rufinus with Jerome's Apology Against Rufinus.: My friendly letter was to prevent discord: the other to crush false opinions.

38. You imagine that I have contrived yet another piece of falsehood, namely, that I have composed a letter to you in my own name, pretending that it was written long ago, in which I make myself appear kindly and courteous; but which you never received. The truth can easily be ascertained. Many persons at Rome have had copies of this letter for the last three years; but they refused to send it to you knowing that you were throwing out insinuations against my reputation, and making up stories of the most shameful kind and unworthy of our Christian profession. I wrote in ignorance of all this, as to a friend; but they would not transmit the letter to an enemy, such as they knew you to be, thus sparing me the effects of my mistakes and you the reproaches of your conscience. You next bring arguments to shew that, if I had written such a letter, I had no right to write another containing many reproaches against you. But here is the error which pervades all that you say, and of which I have a right to complain; whatever I say against the heretics you imagine to be said against you. What! Am I refusing you bread because I give the heretics a stone to crush their brains? But, in order to justify your disbelief in my letter, you are obliged to make out that of pope Anastasius rests upon a similar fraud. On this point I have answered you before. If you really suspect that it is not his writing, you have the means of convicting me of the forgery. But if it is his writing, as his letters of the present year also written against you prove, you will in vain use your false reasonings to prove my letter false, since I can shew from his genuine letter that mine also is genuine.