He now mentions the fruit of their repentance, because the Israelites were beginning at length to attribute just honor to his prophecies. For we know that they trifled carelessly while the Prophets were threatening them. Because, therefore, they were in the habit of destroying confidence in all the servants of God, and of reducing as it were their truth to nothing, the Prophet says, that when they repented they would then perceive that God had not spoken in vain. While they were despising his threats, they did not perceive that they ought therefore to be considered despisers of God. For listening only to men, when they heard Jeremiah or Ezekiel, they thought that they were contending with them only, and could do so with impunity against mere mortals. God therefore, in opposition to this, testifies that he was the chief author. For as error springs from error, they proudly rejected whatever the Prophets said, when they treated it as frivolous and vain. God therefore says: They shall then know that I have not spoken in vain, when I bring upon them this evil. This knowledge, which is produced by real dissatisfaction with self, is very useful. I have said that it is the fruit of repentance, but at the same time it profits the miserable, to humble themselves seriously before God, and to call to memory their own ingratitude: then they perceive what they had never admitted before, that God is trustworthy as well in his threats as in his promises. Hence it happens that they reverently embrace his word which they had formerly despised. He pronounced the same thing previously concerning the reprobate, who, as we have already said, feel God's hand without producing fruit. But because he now speaks of those very few whose conversion he had previously praised, he doubtless comprehends the fear of God under recognition or perception of him. For if all God's threats had been buried, the people could not be thought to have returned into the right way, nor could their conversion have any existence before God. We know that contempt is not free from impious sacrilege, which is now treated of. Therefore, that the sinner may submit himself sincerely to God, this acknowledgment is required, that he should weigh within himself how unworthily and wickedly he had formerly either repudiated or neglected the word of God. In the meantime the Prophet triumphs over the arrogance of those who had wantonly despised the teaching of all God's servants, when he says, they shall feel (or acknowledge) that I Jehovah have not spoken in vain. Since, therefore, the Prophet here depicts as in a painting their late repentance, let us learn to tremble in time at God's threats. Although indeed God does not yet execute his vengeance upon us, yet let us be sure that he does not speak in vain, and let us be alarmed as soon as he shows any sign of his indignation. God indeed testifies that he would be propitious to the Israelites, although their repentance was tardy; but as far as we are concerned, let us repent in time, as I have already admonished, and as soon as God utters his threats, let it be to us just as if their execution were at hand. It follows --