Psalms 144:4

But if this anomalous state of things were uniform in this life, in which, as the sacred Psalmist says, "Man is like to vanity, his days as a shadow that passeth away,"—so uniform that none but wicked men won the transitory prosperity of earth, while only the good suffered its ills,—this could be referred to the just and even benign judgment of God. We might suppose that they who were not destined to obtain those everlasting benefits which constitute human blessedness were either deluded by transitory blessings as the just reward of their wickedness, or were, in God's mercy, consoled them, and that they who were not destined to suffer eternal torments were afflicted with temporal chastisement for their sins, or were stimulated to greater attainment in virtue. But now, as it is, since we not only see good men involved in the ills of life, and bad men enjoying the good of it, which seems unjust, but also that evil often overtakes evil men, and good surprises the good, the rather on this account are God's judgments unsearchable, and His ways past finding out.

Man is made like to vanity: his days pass away like a shadow. Truly our days are like a shadow. I was a little infant, I was a boy, I was a young lad, I was a youth, I was a man, that is, of perfect age, I was of middle age. While I know it not, I am an old man. Death creeps up upon old age. I am changed daily, and I do not perceive that I am nothing. Not for even a single moment of an hour do we stand in our own state, but we are always either growing or diminishing. Therefore man is changed by moments, and while he knows it not, he perishes. I, an old man, recall what I was as a little infant, what I did, how I played, how I ran hither and thither: now I see myself weighed down with excessive burden. His days pass away like a shadow. Our life is a shadow: it is seen, and it has no substance. But that which has no substance quickly passes away. Since therefore man is so wretched, and since he is thus infirm, what do we pray for? what do we ask? what does the prophet say here? what does he pray for?

"Man is made like unto vanity: his days pass away like a shadow." What vanity? Time, which passeth on, and floweth by. For this "vanity" is said in comparison of the Truth, which ever abideth, and never faileth: for it too is a work of His Hand, in its degree. "For," as it is written, "God filled the earth with His good things." What is "His"? That accord with Him. But all these things, being earthly, fleeting, transitory, if they be compared to that Truth, where it is said, "I Am That I Am," all this which passeth away is called "vanity." For through time it vanisheth, like stroke into the air. And why should I say more than that which the Apostle James said, willing to bring down proud men to humility, "What is," saith he, "your life? It is even a vapour, which appeareth for a little time, and then vanisheth away." ...Work then, though it be in the night, with thine hands, that is, by good works seek God, before the day come which shall gladden thee, lest the day come which shall sadden thee. For see how safely thou workest, who art not left by Him whom thou seekest; "that thy Father which seeth in secret may reward thee openly." ...