Psalms 94:11

We may with boldness appeal to God; for he is the almighty Judge by whom every man is judged. Let this encourage those who suffer wrong, to bear it with silence, committing themselves to Him who judges righteously. These prayers are prophecies, which speak terror to the sons of violence. There will come a day of reckoning for all the hard speeches which ungodly sinners have spoken against God, his truths, and ways, and people. It would hardly be believed, if we did not witness it, that millions of rational creatures should live, move, speak, hear, understand, and do what they purpose, yet act as if they believed that God would not punish the abuse of his gifts. As all knowledge is from God, no doubt he knows all the thoughts of the children of men, and knows that the imaginations of the thoughts of men's hearts are only evil, and that continually. Even in good thoughts there is a want of being fixed, which may be called vanity. It concerns us to keep a strict watch over our thoughts, because God takes particular notice of them. Thoughts are words to God.

Whether men admit or deny that God knows, one thing is here declared, namely, that The Lord knoweth the thoughts of man, that they are vanity. Not their words alone are heard, and their works seen, but he reads the secret motions of their minds, for men themselves are not hard to be discerned of him, before his glance they themselves are but vanity. It is in the Lord's esteem no great matter to know the thoughts of such transparent pieces of vanity as mankind are, he sums them up in a moment as poor vain things. This is the sense of the original, but that given in the authorised version is also true —the thoughts, the best part, the most spiritual portion of man's nature, even these are vanity itself, and nothing better. Poor man! And yet such a creature as this boasts, plays at monarch, tyrannises over his fellow worms, and defies his God! Madness is mingled with human vanity, like smoke with the fog, to make it fouler but not more substantial than it would have been alone. How foolish are those who think that God does not know their actions, when the truth is that their vain thoughts are all perceived by him! How absurd to make nothing of God when in fact we ourselves are as nothing in his sight.