Isaiah 55:8

He speaks these words clearly to the believers in the gospel that he delivered to the godless and lawless ones who were turning to him from the nations, presenting the word that was there in the beginning and is now coming down from the Father above like rain and snow in its descent to human beings, inasmuch as he makes their souls watered and fruit-bearing.… It is as though these words come out of Christ's own mouth, so that there is no need to think of the spoken word reexpressed among us, since here is a physical mouthpiece for God.

"For my counsels are not as your counsels." … Now if we admit to our favor household slaves when they have offended against us, on their promising to become better, and place them again in their former position and sometimes even grant them greater freedom of speech than before, much more does God act thus. For if God had made us in order to punish us, we might well have despaired and questioned the possibility of our own salvation. But if he created us for no other reason than his own good will, and with a view to our enjoying everlasting blessings, and if he does and contrives everything for this end, from the first day until the present time, what is there which can ever cause us to doubt? Have we provoked him severely, in a way no other person did? This is just the reason why we ought specially to abstain from our present deeds and to repent for the past and exhibit a great change. For the evils we have once perpetrated cannot provoke him so much as our being unwilling to make any change in the future. For to sin may be a merely human failing, but to continue in the same sin ceases to be human and becomes altogether devilish.

Do not want to be more merciful than God, or rather, if you wish it, you will not be able, not even in the least degree. How should you? As far as the heaven is from the earth, Scripture says, so far are My counsels from your counsels: and again, If ye, He says, being evil, know how to give good gifts unto your children, how much more your heavenly Father? But in fact this talk is mere pretext and subterfuge. Let us not prevaricate with God's commandments.

For my thoughts are not your thoughts: nor are your ways my ways, says the Lord. For as the heavens are exalted above the earth, so are my ways exalted above your ways, and my thoughts above your thoughts. LXX: For my thoughts are not as your thoughts: nor are your ways as my ways, says the Lord. But as far as heaven is distant from the earth, so far is my way distant from your ways, and your thoughts from my thought. Do not think, he says, that what I promise is difficult, and let it not seem incredible to you that the ungodly and the unrighteous can be saved, whether the people of the Jews or all those among the nations who did not know God: consider this, that there is a great difference between my counsels and yours, and as great a diversity of will as of nature (Prov 19). For many are the thoughts in the heart of a man, but the counsel of the Lord abides forever. You, as men, often repenting of a promise, have overturned your old will with a new will. For the Lord scatters the counsels of the nations, and rejects the thoughts of the peoples, and makes void the wills of princes (Ps 32 [33]); but the thoughts of His heart are from generation to generation, and whatever He has decreed cannot be changed.

God brings salvation to the human race in diverse and innumerable methods and inscrutable ways. He stirs up some, who already want it and thirst for it, to greater zeal, while other even in their resistance, he forces against their will. Sometimes he gives his assistance in the fulfillment of those things which he sees that we desire for our good, while at other times he instills in us the beginnings of holy desire and grants both the beginning of a good work and perseverance in it.… The blessed apostle, reflecting on the manifold bounty of God's providence as he sees that he has fallen into some vast and boundless ocean of God's goodness, exclaims: "O the depth of the riches of the wisdom and knowledge of God! How inscrutable are the judgments of God and his ways past finding out! For who hath known the mind of the Lord?" Whoever then imagines that he can by human reason fathom the depths of that inconceivable abyss, will be trying to explain away the astonishment at that knowledge, at which that great and mighty teacher of the gentiles was awed. For if a person thinks that he can either conceive in his mind or discuss exhaustively the designs of God through which he brings salvation to human beings, he certainly impugns the truth of the apostle's words and asserts with profane audacity that his judgments can be scrutinized and his ways searched out. The Lord also witnesses to this when he says, "For my thoughts are not your thoughts, neither are your ways my ways."

Fourth, he excludes the obstacle to mercy: for my thoughts are not your thoughts, as if to say: you are wicked, I am loving; you think of vengeance, I think of mercy: is it my ways that are not right, and are not rather your ways perverse? (Ezek 18:25).