Nicene and Post-Nicene Fathers, Vol. III:
Moral Treatises of St. Augustin: Section 1

1. A great deal for me to read hast thou sent, my dearest brother Consentius: a great deal for me to read: to the which while I am preparing an answer, and am drawn off first by one, then by another, more urgent occupation, the year has measured out its course, and has thrust me into such straits, that I must answer in what sort I may, lest the time for sailing being now favorable, and the bearer desirous to return, I should too long detain him. Having therefore unrolled and read through all that Leonas, servant of God, brought me from thee, both soon after I received it, and afterwards when about to dictate this reply, and having weighed it with all the consideration in my power, I am greatly delighted with thy eloquence, and memory of the holy Scripture, and cleverness of wit, and the resentment with which thou bitest negligent Catholics, and the zeal with which thou gnashest against even latent heretics. But I am not persuaded that it is right to unearth them out of their hiding places by our telling lies. For to what end do we take such pains in tracking them out and running them down, but that having taken them and brought them forth into open day, we may either teach them the truth, or at least having convicted them by the truth, may not allow them to hurt others? to this end, therefore, that their lie may be blotted out, or shunned, and God’s truth increased. How then by a lie shall I rightly be able to prosecute lies? Or is it by robbery that robberies and by sacrilege that sacrileges, and by adultery that adulteries, are to be prosecuted? “But if the truth of God shall abound by my lie,” are we too to say, “Let us do evil that good may come?” 2384 A thing which thou seest how the Apostle detesteth. For what else is, “Let us lie, that we may bring heretic liars to the truth,” but, “Let us do evil that good may come?” Or, is a lie sometimes good, or sometimes a lie not evil? Why then is it written, “Thou hatest, Lord, all that work iniquity; Thou wilt destroy all that speak leasing.” 2385 For he hath not excepted some, or said indefinitely, “Thou wilt destroy them that speak leasing;” so as to permit some, not all, to be understood: but it is an universal sentence that he hath passed, saying, “Thou wilt destroy all who speak leasing.” Or, bep. 482 cause it is not said, Thou wilt destroy all who speak all leasing, or, who speak any leasing whatsoever; is it therefore to be thought that there is place allowed for some lie; to wit, that there should be some leasing, and them who speak it, God should not destroy, but destroy them all which speak unjust leasing, not what lie soever, because there is found also a just lie, which as such ought to be matter of praise, not of crime?

Footnotes

Rom. 3:7, 8Rom. 3:7, 8

Ps. 5:6, 7Ps. 5:6, 7. [See R.V.] “Thou wilt destroy them that speak a lie,” Heb. πάντας τοὺς λαλοῦντας τὸ ψεῦδος, LXX.