3 Yet, as I see that after the first opinion expressed in your letter, you have been disturbed subsequently by letters of Novatian, I assert this first of all, dearest brother, that grave men, and men who are once established upon the strong rock with solid firmness, are not moved, I say not with a light air, but even with a wind or a tempest, lest their mind, changeable and uncertain, be frequently agitated here and there by various opinions, as by gusts of wind rushing on them, and so be turned from its purpose with some reproach of levity.
That the letters of Novatian may not do this with you, nor with any one, I will set before you, as you have desired, my brother, an account of the matter in few words. And first of all indeed, as you also seem troubled about what I too have done, I must clear my own person and cause in your eyes, lest any should think that I have lightly withdrawn from my purpose, and while at first and at the commencement I maintained evangelical vigour, yet subsequently I seem to have turned my mind from discipline and from its former severity of judgment, so as to think that those who have stained their conscience with certificates, or have offered abominable sacrifices, are to have peace made easy to them. Both of which things have been done by me, not without long-balanced and pondered reasons.
Source: The Epistles of Cyprian (New Advent)