Moralia in Job 1162

The same place. — 'And it shall not be searched out, when his voice shall have been heard.' 41. By what means this voice instills itself into the ears of the heart is unknown. — The voice of the Lord is heard when the inspiration of his grace is conceived in the mind, when the insensibility of hidden deafness is broken, and the heart, aroused to the zeal of the highest love, is penetrated by the cry of an inward power. But this voice of the supervening Spirit, which instills itself into the ears of the heart, not even the very mind which has been illumined through it can search out. For it cannot ponder by what passages the invisible power flows into it, by what means it comes to it, by what means it withdraws. Whence also it is well said through John: 'The Spirit breatheth where it will; and thou hearest its voice, but knowest not whence it cometh, and whither it goeth' (John 3:8).

For to hear the voice of the Spirit is to rise up, by the force of inward compunction, into the love of the invisible Creator. But no one knows whence it comes, because it is unknown by what occasions it pours itself into us through the mouths of preachers. And no one knows whither it goes, because when many hear one preaching, it assuredly cannot be understood whom it, deserting, casts away, or into whose heart it, entering, comes to rest.

For one thing is done outwardly, but not through this are the hearts of the hearers penetrated in one manner, because he who invisibly regulates visible things plants incomprehensibly in human hearts the seeds of the thing caused. Hence it is that, at the raising of Lazarus, certain believed, and yet very many of the Jews were moved to the zeal of persecution by that same raising (John 11:45). One and the same miracle, therefore, which to some afforded the light of faith, blinded others, through the darkness of envy, in the light of the mind. Hence it is that both thieves saw the same death of the Redeemer, and one like unto their own death (Luke 23:39); but the one, growing proud, did not fear to provoke him with insults, whom the other, fearing, honored;

and in one thing the thought of the two was not one, because the eternal Arbiter, invisibly regulating, distinguished it. But because the modes of the hidden inspiration cannot be comprehended by our thought, assuredly the traces of the divine voice are unknown. Well therefore is it said: 'And it shall not be searched out, when his voice shall have been heard.' Whence also it is still further subjoined: