The general purport of the expression "a man of the world" will be allowed to be that which is evidently David's meaning in the text: a man who has no spiritual yearnings, no holy aspirations; a mere earthworm, selfish, sordid, and greedy of gain; whose supreme and only thought is to make money, and have his nest well feathered here.
I. Think of the portion which belongs to men of the world. There is not a greater mistake than to imagine that you will be heart-rich as soon as you become purse-rich. Riches do make happy; but it is not the riches of the pocket, but the riches of the mind and heart: the riches of taste, of culture, of affection, and, above all, the riches of God's grace, which impart capacities of deep and intense enjoyment, otherwise unknown. It is a very solemn thought for any of you who are mere "men of the world" that, though you should be ever so successful, though your gains indeed should be far beyond your expectation, what you have got is only "a portion for this life."
II. Look, next, at the contrast as suggested by David's words in the next verse: "As for me, I will behold Thy face in righteousness; I shall be satisfied when I awake with Thy likeness." There were two things in which he placed the secret of true happiness: the one was seeking God as his Saviour, and the other was being made like Him in character. (1) "I will behold Thy face in righteousness." When reference is made to the "face of God," there is generally an allusion to Jesus Christ, His Son. The Psalmist means that he will fix his eye on God as reconciled to him through the righteousness of the Redeemer. This is the first secret of a happy life. (2) Satisfied when? "When I awake." The moment of resurrection will be the first moment in our history when, in the fullest, amplest sense of the word, we shall be able to say, "I am satisfied! I have all that I can desire!"
J. Thain Davidson, The City Youth,p. 169.
Reference: Psalms 17:14. Expositor,3rd series, vol. v., p. 308.