Thomas a Kempis preaches about the importance of trusting in God's judgment over the opinions of men, emphasizing the need for humility, endurance, and reliance on God's mercy. He highlights that true strength comes from God and that seeking validation from the world reveals a lack of true humility and death to worldly desires. Kempis encourages seeking God in every decision, acknowledging His omniscience and righteous judgment that surpasses human understanding.

THE VOICE OF CHRIST MY CHILD, stand firm and trust in Me. For what are words but words? They fly through the air but hurt not a stone. If you are guilty, consider how you would gladly amend. If you are not conscious of any fault, think that you wish to bear this for the sake of God. It is little enough for you occasionally to endure words, since you are not yet strong enough to bear hard blows. And why do such small matters pierce you to the heart, unless because you are still carnal and pay more heed to men than you ought? You do not wish to be reproved for your faults and you seek shelter in excuses because you are afraid of being despised. But look into yourself more thoroughly and you will learn that the world is still alive in you, in a vain desire to please men. For when you shrink from being abased and confounded for your failings, it is plain indeed that you are not truly humble or truly dead to the world, and that the world is not crucified in you. Listen to My word, and you will not value ten thousand words of men. Behold, if every malicious thing that could possibly be invented were uttered against you, what harm could it do if you ignored it all and gave it no more thought than you would a blade of grass? Could it so much as pluck one hair from your head? He who does not keep his heart within him, and who does not have God before his eyes is easily moved by a word of disparagement. He who trusts in Me, on the other hand, and who has no desire to stand by his own judgment, will be free from the fear of men. For I am the judge and discerner of all secrets. I know how all things happen. I know who causes injury and who suffers it. From Me that word proceeded, and with My permission it happened, that out of many hearts thoughts may be revealed. I shall judge the guilty and the innocent; but I have wished beforehand to try them both by secret judgment. The testimony of man is often deceiving, but My judgment is true -- it will stand and not be overthrown. It is hidden from many and made known to but a few. Yet it is never mistaken and cannot be mistaken even though it does not seem right in the eyes of the unwise. To Me, therefore, you ought to come in every decision, not depending on your own judgment. For the just man will not be disturbed, no matter what may befall him from God. Even if an unjust charge be made against him he will not be much troubled. Neither will he exult vainly if through others he is justly acquitted. He considers that it is I Who search the hearts and inmost thoughts of men, that I do not judge according to the face of things or human appearances. For what the judgment of men considers praiseworthy is often worthy of blame in My sight. THE DISCIPLE O Lord God, just Judge, strong and patient, You Who know the weakness and depravity of men, be my strength and all my confidence, for my own conscience is not sufficient for me. You know what I do not know, and, therefore, I ought to humble myself whenever I am accused and bear it meekly. Forgive me, then, in Your mercy for my every failure in this regard, and give me once more the grace of greater endurance. Better to me is Your abundant mercy in obtaining pardon than the justice which I imagine in defending the secrets of my conscience. And though I am not conscious to myself of any fault, yet I cannot thereby justify myself, because without Your mercy no man living will be justified in Your sight.