Nicene and Post-Nicene Fathers, Vol. II:
City of God: Chapter 14

Chapter 14.—An Explanation of What is Said of the Devil, that He Did Not Abide in the Truth, Because the Truth Was Not in Him.

Moreover, as if we had been inquiring why the devil did not abide in the truth, our Lord subjoins the reason, saying, “because the truth is not in him.”  Now, it would be in him had he abode in it.  But the phraseology is unusual.  For, as the words stand, “He abode not in the truth, because the truth is not in him,” it seems as if the truth’s not being in him were the cause of his not abiding in it; whereas his not abiding in the truth is rather the cause of its not being in him.  The same form of speech is found in the psalm:  “I have called upon Thee, for Thou hast heard me, O God,” 478 where we should expect it to be said, Thou hast heard me, O God, for I have called upon Thee.  But when he had said, “I have called,” then, as if some one were seeking proof of this, he demonstrates the effectual earnestness of his prayer by the effect of God’s hearing it; as if he had said, The proof that I have prayed is that Thou hast heard me.

Footnotes

Ps. 17.6.